The PAM project Personalised Ambient Monitoring: aiding those with Bipolar Disorder Sally Brailsford John Crowe Christopher James Evan Magill The PAM project The PAM project Enabling health, independence and wellbeing.

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Transcript The PAM project Personalised Ambient Monitoring: aiding those with Bipolar Disorder Sally Brailsford John Crowe Christopher James Evan Magill The PAM project The PAM project Enabling health, independence and wellbeing.

Slide 1

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 2

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 3

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 4

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 5

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 6

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 7

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 8

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 9

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 10

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 11

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 12

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 13

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 14

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 15

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 16

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 17

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 18

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 19

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 20

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 21

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 22

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 23

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 24

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 25

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 26

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 27

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 28

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 29

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 30

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 31

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 32

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 33

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 34

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 35

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 36

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 37

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 38

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 39

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 40

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 41

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 42

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 43

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 44

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 45

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 46

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 47

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 48

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 49

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 50

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 51

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 52

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 53

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 54

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 55

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 56

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 57

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 58

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 59

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 60

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 61

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 62

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 63

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 64

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 65

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 66

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 67

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 68

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 69

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 70

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72


Slide 71

The PAM project

Personalised Ambient Monitoring:

aiding those with Bipolar Disorder
Sally Brailsford

John Crowe
Christopher James
Evan Magill

The PAM project

The PAM project
Enabling health, independence and
wellbeing for psychiatric patients through
Personalised Ambient Monitoring

2

The PAM project

A sandpit project
• Funded by the Engineering and Physical Sciences Research
Council
• Sandpit theme: “Bringing Care to the Patient”

3

The PAM project

The PAM team
• Sally Brailsford, Southampton
Behavioural
Analysis

• John Crowe, Nottingham
• Christopher James, Southampton (PI)
• Evan Magill, Stirling
Sensors

PAM

Ambient
Monitoring

• plus 4 PhD students
– Syed Mohiuddin, Pawel Prociow,
James Amor and Jesse Blum

Operational
Research
4

The PAM project

PAM external steering group
• Ms Sylvia Wyatt, Future Healthcare Network, NHS Scotland
• Dr Amy Drahota, Research Fellow, University of Portsmouth
• Mr Peter Jones, Community mental health nurse, Lancashire Care NHS
Trust
• Dr Paul Courtney, Consultant Psychiatrist, Hampshire Partnership
Trust
• Mr Richard Barritt, Chief Executive, Solent MIND

• Mr James Stubbs, Service User Representative

5

The PAM project

The aims of PAM
• To build a system of unobtrusive sensors, linked (through a
standard mobile phone) to a remote computer system,
which automatically monitors the activity patterns of
people with mental health problems
• To determine whether it is possible to use such a system to
obtain ‘activity signatures’ in a manner which is acceptable
to the patient and can provide useful information about the
trajectory of their health status
• And if this is so, to determine how this information can best
be used to maintain health and aid independence
6

The PAM project

Bipolar Disorder
• Severely disabling mental illness which affects functionality,
relationships, employment and quality of life; affects 2% of the
UK population (MHF, 2006)
• Bipolar disorder is the 6th most common disabling illness
worldwide (WHO, 2004)
• In 2002, the estimated annual cost to the UK NHS of managing
bipolar disorder was £199M, of which £70M was spent on
hospital admissions (Gupta and Guest, 2002)
• Many pharmacological treatments are available but these can
have unpleasant side-effects and adherence is often poor, leading
to hospital admission
7

The PAM project

How does BD alter lifestyle?
Manic

Depressive

Euphoric behaviour

Low mood

Increased (excessive)
social activity

Lack of interest in social
interaction

Psychomotor agitation

Psychomotor retardation

Sleep deprivation

Insomnia

Flight of ideas

Concentration problems

The PAM project

Managing Bipolar Disorder
• Most patients want to manage their own condition, using
medication only when necessary
• Motivated patients of above-average intelligence, interested
in self care and independence
• Early warning signs or prodromes can be detected while
patient is still “self-aware” and can take action (seek
medical help, start medication etc) to avoid hospital
admission
• Paper-based “mood diaries” shown to be effective in trials
9

The PAM project

Problems with paper-based systems
• Do not provide a sense of control over daily life
• Patients complain about vigilance and energy required
• Problems with accuracy, completeness and honesty of
patient-reported data
• Patients may forget to document important details
• Comorbidity and drug response go unmeasured
• No reduction in depressive relapses (Perry et al, 1999)

10

The PAM project

The aim of PAM
• To use a system of electronic sensors to provide an
automated equivalent of a mood diary, which alerts the
patient to a change in activity pattern which could signal
the onset of a bipolar episode
• Patient would be sent an SMS alerting them to a possible
change, which they could then act on (if they chose)
• PAM is mainly aimed at people who live alone
• Aim is to identify a baseline “activity signature” and then
identify significant deviations from this
11

Device Nodes
• Worn
– Mobile Phone
• Questionnaire
• Gateway Application
– GPS Transceiver
– Wearable Accelerometer
– Wearable Microphone
– Wearable Light Sensor
• Environmental








Microphone
Light Sensor
Passive Infrared Sensors
Micro-switches
Bed Sensor
Camera
Infrared Receiver For Remote Control

The PAM project

The PAM project

Wearable sensor set
User input:
• General health
questionnaires
• Mood selfassessment

Wearable Node
•Acceleration
•General light level
•Artificial light level
•Ambient sound
properties

GSM
location

GPS
module
XYZ
accelerometer

Internal
accelerometer

Bluetooth
Encounters*

- Bluetooth

- 3G / GPRS

- User input

-Internal

Environmental sensor set
Environmental processing
unit
•Processing
•Storage
•Backup
•Upload

Wide-angle
Camera
PIR
sensors

Home appliances
monitoring
•Microwave
•Refrigerator
•Oven

Environmental Node
Monitoring of:
•Remote control activity
Main and cupboard doors.
•General light level
•Artificial light level
•Ambient sound.
- Bluetooth

The PAM project

Bed occupancy
sensor

- WiFi

- 433 MHz RF

The PAM project

Example data – wearable light levels

General light

Artificial light

Working

Bus awaiting

Bus awaiting

Commuting

Walking

Home

The PAM project

Threads of research activity
• The four centres collaborated across the project but we
gravitated towards independent themes (as required by the
four PhD students)

• accelerometry & behaviour analysis
• outside the home
• BD modelling
• rule-based sensor network

The PAM project
accelerometry & behaviour analysis

accelerometry & behaviour analysis

The PAM project
accelerometry & behaviour analysis

Accelerometry & Behavioural analysis
• Determine what a person is doing (sleeping, eating,
restlessly pacing around, etc) by feature extraction
algorithms on sensor data (e.g. the “neuroscale” algorithm)
• Develop an “activity signature” for that individual,
describing their normal activity pattern when well
• Develop a set of decision rules which determine whether an
individual’s current activity is “normal” – for them – or
may indicate the potential onset of a prodrome

19

The PAM project

Tri-axial accelerometry

accelerometry & behaviour analysis

Walk
12

Walk
25

walking

10

20

15
8
10

6

5

0
4
-5
2
-10

0

0

0.5

1

1.5

2

2.5

-15
-800

-700

-600

-500

-400

-300

-200

-100

0

100

-200

-100

0

100

4

x 10

Lecture
12

25

at a lecture

10

Lecture

20

15
8

Acceleration

10

6

5

0
4
-5
2
-10

0

0

2000

4000

6000
8000
Samples (1 Hz)

10000

12000

activity over time

14000

-15
-800

-700

-600

-500

-400

-300

clustered activity

20

The PAM project
outside the home

outside the home

The PAM project

Outside the home
Example: tracking movement & position

outside the home

Off-the-shelf GPS module

BT enabled accelerometer

logfile.txt
13
13
13
13

Feb
Feb
Feb
Feb

2010
2010
2010
2010

13:06:41;
13:06:42;
13:06:44;
13:06:45;

G;
A;
A;
A;

5256.0723; -112.181; 0.0;
0.044; -0.888; 0.484;
0.036; -0.892; 0.492;
0.036; -0.892; 0.496;

The PAM project
outside the home

Positional data and pre-processing

The PAM project
outside the home

Identifying meaningful locations

Activity data – Bluetooth

The PAM project
outside the home

• Participants on average encountered more than 1000
unique Bluetooth devices of which:





80% were one-off encounters
15% were “occasional” (1-10) encounters
4% were “frequent” (10-40) encounters
1% were “regular” (40 or more) encounters

• This data can be used to monitor social interactions and
enhance location information

The PAM project
BD modelling

BD Modelling

The PAM project
BD modelling

Operational Research modelling of PAM
• Aim is to develop a “natural history” model for BD and use
it to test the sensitivity and specificity of the PAM
algorithms for detecting change in a patient’s health status,
in the context of:– A random (personalised) selection of sensors
– Unknown reliability of the chosen sensors and the
computer network system

– Occasional failure (or deliberate removal) of a sensor
– Variety in patient behaviour, in all states of health
27

The PAM project
BD modelling

Challenges for modelling BD
• No OR modelling approach of BD in the literature, although
some Markov models for depression (Patten et al, 2005)
• No universally accepted staging models for BD found in the
medical literature
• Symptoms vary among patients ; and patients may exhibit
mixed behaviour (manic and depressed)

• Lack of easily measurable criteria
• Took advice from clinical psychiatrist on our Steering
Group
28

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Final state transition model


=0

=1

• The parameter  represents mental health state: totally
depressed ( = 0), “normal” or healthy ( ≈ 0.5) and totally
manic ( = 1)
• Each day, with a certain probability, the person may either
stay in the same state, or progress to an adjacent state, in
steps of 0.01
30

The PAM project
BD modelling

An illustrative sample path for λ
1.2

1

Lambda values

0.8

0.6

0.4

0.2

0
0

100

200

300

Days

400

500

600

31

Normal
Depressed
Manic

Hours of sleep
6
10
2

Phone calls
4
1
12

The PAM project
BD modelling

Sleep

Phone

14.00

12.00

Hours / Calls

10.00

8.00

6.00

4.00

2.00

0.00
0.00

0.20

0.40

0.60

0.80

1.00

1.20

Lamda

32

The PAM project
BD modelling

PAM-detected physical activity levels
during various mood states
Physical Activity Levels (PAL)
PAM detected PAL
2.6

2.4

Physical Activity Levels

2.2

2

1.8

1.6

1.4

1.2

1
0

100

200

300

Days

400

500

600

33

The PAM project
rule-based sensor network

rule-based sensor networks

The PAM project
rule-based sensor network

Programming sensor networks (PROSEN)
• distribute rules to rule engines embedded in smart sensors
• flexible programming
• support for run-time updating of rules
• aids personalisation and changing mental states
• initial work in a wind farm setting ….

The PAM project

PROSEN & REED

rule-based sensor network

• REED (Rule Execution and Event Distribution):

– supports the distribution of rules and trigger events
– employs a rule-based paradigm :
• allows sensor networks to be programmed at run time
• allows allow sensor network behaviour to be changed
at run time
– allows subscribe-notify service to be constructed
– potential for processing, filtering and collating data

The PAM project

Communications paradigm

rule-based sensor network

• Low-level decision and event driven
• Interact by sending/receiving decisions and events
• Low-level decision:


Event received from:
• components in PN
• Neighbour PN
• Policy server

Test of a local
state

Executed if the condition
is true
• manipulate/store local
data
• generate events
• may generate low-level
decisions

The PAM project

REED Middleware architecture
Sensor diagnostics

Low-level AI
(“novelty” filter)

rule-based sensor network

Sensor controller


Middleware Interface
Decision Space management
Event
Initial default
decisions
<“power up”, true,
<“temp
sensor
reading
“sending
HELLO
update”,
“temp < -20”,
event”>
“send ‘temp too low’ event
to Policy server”>
Event

Function call

Decision Space
Decision

event

condition

action


event

condition action

Decision

Event

Decision

Operation System Interface

Operation
System

Processing

Storage

Communications

The PAM project

Mobile phone-centric
sensor-based care system

rule-based sensor network

39

The PAM project
rule-based sensor network

Backend – Gateway Connection

The PAM project
rule-based sensor network

Network Interface

The PAM project
rule-based sensor network

Mobile Phone Based Body Area Network

The PAM project
rule-based sensor network

PAM Sensor Reading (PSR)

Frequency="1" Unitoftime="4s" Id="1251993327994" />
50.936348, -1.393458, 0.0, 4.0
Frequency="1" Unitoftime="s" Id="1251993354943" />
Frequency="1" Unitoftime="s" Id="1251993354952" />
-0.5083, 1.7986, 0.0782
-0.1173, 1.1339, 0.2346
-0.0782, 0.8993, 0.1173
2.0, 0.0
...

The PAM project
rule-based sensor network

MOBILE RULE-BASED APPLICATIONS
• Custom Symbian S60 Java ME applications installed on the
mobile phone interfaced with m-Prolog. (Also Sony-Ericsson)
• PAM-Gateway
– Control data capture from wearable units (such as GPS,
accelerometer, ambient light and sound levels)
• PAM-Transfer
– Perform automatic mobile to PC data transmission
• PAM-Q

– Dynamically adjustable questionnaires

The PAM project
rule-based sensor network

RELIABILITY AND ACCEPTABILITY ISSUES
• Mobile phone battery life
• On-body gateway disconnection
• On-body device form factor issues
• Environmental sensor reliability issues
• Rule coherence

The PAM project

Internal GPS: 5 hours
@ 0.68 w

POWER ISSUES

rule-based sensor network

BT, but no storage:
7.5 hours @ 0.48 w

1.8
1.6
1.4

1
0.8

Profile 1
Profile 2

0.6

Profile 3
0.4

Profile 4

0.2

0
TIMESTAMP (s)
33.25
36.75
40.25
43.75
47.25
50.75
54.25
57.75
61.25
64.75
68.25
71.75
75.25
78.75
82.25
85.75
89.25
92.75
96.25
99.75
103.25
106.75
110.25
113.75
117.25
120.75
124.25
127.75
131.25
134.75
138.25
141.75
145.25
148.75
152.25
155.75
159.25
162.75
166.25
169.75
173.25
176.75

Power (W)

1.2

BT, and storage: 5.5
hours @ 0.67 w

No BT & no user
applications: 9
hours @ 0.41 w

The PAM project
rule-based sensor network

Rule Coherence
• when rules are:
– changing over time
– possibly unique for particular individuals
– originating from different stakeholders
• how can we ensure the integrity of the rules
– in particular the lack of conflicts between rules

47

Example: “traditional” feature interaction

The PAM project
rule-based sensor network

Alice

OCS

Bob

CFx

X
Charlie

• Alice cannot call Charlie
– Originating Call Screening (OCS)
• If Alice calls Bob

– Bob’s Call Forwarding transfers call to Charlie
48

The PAM project

classes of feature interactions
1.

MAI: Two (or more) features
control the same device
(Multiple Action Interaction)

Power
F
Saving

off

rule-based sensor network

heater
D

Env
F
cntrl

2.

STI: One event goes to
different services which
perform different conflicting
actions (Shared Trigger
Interaction)

temp
D

hot

airF
con

wind
F
cntrl
49

The PAM project

classes of feature interactions
3.

SAI: A service performs an action on a device which triggers another
feature. The chain might involve any number of links (Sequential
Action Interaction, Loops)

Env
F
Cntrl

4.

rule-based sensor network

close

blinds
move
D

!

alarm
F

MTI: The existence of one feature prevents the another one from
operating. (Missed Trigger Interaction)

Power
F
Saving

off

temp
D

cold

heat
F
cntrl

50

Conflict Analysis

The PAM project
rule-based sensor network

• Offline and online analysis
looking for conflicts
between device rules
• Like FI for call control
• Searching for 5 types of
conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were
developed to explore the
conflicts
Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
51

The PAM project
rule-based sensor network

initial results
• 867 tests for combining:

– shared trigger,
– multiple action, and
– sequential action.

• that is; from 17 features against each other and
themselves across the three criteria.
• 410 conflicts detected

• currently being analysed for patterns

{jmb, ehm}@cs.stir.ac.uk

52

The PAM project
in conclusion

in conclusion

The PAM project
in conclusion

PAM in practice
• A short technical trial of PAM was been carried out on the
four PhD students
• NHS ethics approval obtained for a small patient study
(max 4 patients) of PAM: completed in Southampton but
still under way in Scotland
• Many practical aspects highlighted in clinical study!

• Further technical developments under discussion
• Further collaborations planned
54

The PAM project
in conclusion

Moving forward – other PAM like projects
• PSYCHE (Personalised monitoring SYstems for Care in
mental HEalth) project develops a personal, cost-effective,
multi-parametric monitoring system based on textile
platforms and portable sensing devices for the long term
and short term acquisition of data from selected class of
patients affected by mood disorders.

• http://www.psyche-project.org

55

MONARCA

The PAM project
in conclusion

• MONitoring, treAtment and pRediCtion of bipolAr disorder
episodes (Monarca)
• EC funding of near €4m
• An example of recently funded EU projects in this field.
• Monarca is investigating aspects of bipolar disorder disease
by adopting a holistic approach to its assessment, treatment
and self-management. The project focuses on objective
assessment and prediction of bipolar disorder episodes and
aims to advance the discovery of new markers for this
disease.
56

OPTIMI

The PAM project
in conclusion

• Online Predictive Tools for Intervention in Mental Illness

• EU funding
• The Neuroscience Institute at the University of Bristol.
• The aim is to develop tools to perform predictions based on
early identification of the onset of an illness by monitoring
poor coping behaviour.
• The system will study an individual's behaviour patterns
over a sustained period and spot any baseline changes
suggesting they are becoming unwell.
• Will use wearable sensors and sensors fitted to domestic
appliances to measure activity levels. EEG readings, voice
analysis and physical activity analysis will be used.

57

The PAM project

Thank you for listening

58

The PAM project

State-of-the-art Health Sensor Networks
• Wearable Sensor Networks & Body Sensor Networks for medical and
psychiatric monitoring is active an research area:
– Alarm-Net
– CodeBlue
– Care in the Community
– UbiMon
– MobiCare
– LiveNet

The PAM project
BD modelling

Initial conceptual model of BD
“Normal”

Manic

Depressed

The PAM project
BD modelling

Using λ to model behaviour

 2  1
4 1   N  2  3  1 D       M
2 2




2



N = value of parameter X when normal (λ close to 0.5)
D = value of parameter X when depressed (λ close to 0)
M = value of parameter X when manic (λ close to 1)
where X = number of phone calls made daily, or number of
hours of sleep per 24-hour period
61

The PAM project
BD modelling

Time t
in days

Individual’s activity when
normal, manic or depressed

Mental health
state λ(t)

Actual activity
on day t

PAM-detected
activity on day t

Sensor
accuracy and
reliability

Decision rules

Trigger alert?

The PAM project
BD modelling

Patient types (the P in PAM)
• Different people will accept different levels of monitoring
• Defined on the basis of prodromes rather than sensors
– Patient types 1 to 10 chose a selection of two different prodromes

– Patient types 11 to 19 chose a selection of three different prodromes
– Patient types 20 to 24 chose a selection of four different prodromes
– Patient type 25 chose all five

• Pragmatic choice given vast number of combinations of
actual sensors

63

The PAM project
BD modelling

Model outputs
• True positive alerts (TP) and false positive alerts (FP)
• True negatives (TN) and false negatives (FN)
• Average number of days to detect the onset of a depressive
episode (ODE)
• Average number of days to detect the onset of a manic
episode (OME)
• The ideal would be a very low FP, a very high TP, and very
low ODE and OME
64

The PAM project
BD modelling

Example Results for Dataset
Patient types

Choices of prodromes

Minimum no. of sensors
required

ODE
(days)

OME
(days)

TP (%)

FP (%)

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

5.90

2.64

87.48

2.12

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor

8.10

3.12

85.22

0.85

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Camera; Cupboard door
sensors

8.17

3.54

84.16

1.30

8.37

4.01

83.65

1.05

Activity level
Sleep

Type 25

Talkativeness
Social energy
Appetite
Activity level

Type 20

Sleep
Talkativeness
Social energy
Activity level

Type 22

Sleep
Social energy
Appetite
Activity level

Type 21

Sleep
Talkativeness

Accelerometer; GPS; TV usage sensor;
Pressure mat; Light sensor;
Microphone; Phone sensor; Camera;
Cupboard door sensors

Appetite

65

The PAM project

PAM Infrastructure Vision



The PAM project
BD modelling

Implications
• PAM was found to be inadequate for almost all the personalised choices
of two prodromes only
• PAM was found to be efficient for most choices of three prodromes.
• PAM was found to be less effective for a few specific combinations of
personalised prodromal choices, especially ‘sleep’, ‘talkativeness’ and
‘social energy’, or ‘talkativeness’, ‘social energy’ and ‘appetite’, because
these prodromes were associated with relatively few observable
behaviours

• To be able to effectively offer choices such as these, the PAM system
would need to increase the number of their associated observable
behaviours
67

The PAM project

example: Context Triggering System
1 % respond to changes upon receiving contextual information
2 cds_cts(Trigger,T) :3 T2 is T+1,
4 assert(happens(listen_for_connection,T)),
5 assert(happens(make_connection,T)),
6 assert(happens(receive_data,T)),
7 assert(happens(checks_data,T)),
8 assert(happens(listen_for_connection,T2)),
9 ((

10 holdsAt(message(Trigger), T2),
11 assert(initiates(checks_data,prompt(Trigger),T)),
12 assert(terminates(checks_data,message(Trigger),T))
13 );
{jmb, ehm}@cs.stir.ac.uk

14 assert(terminates(checks_data,message(Trigger),T))).

68

The PAM project

Conflict Analysis
• Offline and online analysis
looking for conflicts between
device rules
• Like FI for call control
• Searching for 5 types of conflict:

– STI, SAI, LI, MAI, MTI
• 12 case studies were developed
to explore the conflicts

Missed Trigger Interaction occurs when the
Context Triggering rules delay the activation
of a home gateway.
{jmb, ehm}@cs.stir.ac.uk

69

The PAM project

Detection Approach
• Prolog-based framework
• Evaluates pairs of feature
rules to determine whether
they are concordant or
conflict

Example diagram describing MTI
70
conflict detection rule
{jmb, ehm}@cs.stir.ac.uk

The PAM project

Device Priority Approach to Resolution
• Allows precedence across devices without their knowledge of each
other
• How it works

1.

Resolver receives a list of conflicts, device priorities and
device rules


Priorities are declared as ordered preference lists of
particular properties (such as power efficiency,
bandwidth minimisation, data integrity, etc)
• Rules may be listed for each property
2. Resolver determines rules that should be disabled

{jmb, ehm}@cs.stir.ac.uk

71

The PAM project

Analysis Results

MTI Case Study

Notification suppression

Notification suppression

MTI

Notification suppression

Response prompting

MTI

Response prompting

Notification suppression

MTI

Response prompting

Response prompting

MTI

SAI Case Study
Data Transfer

Data Transfer

SAI

Data Transfer

Data Redirect

SAI

Data Redirect

Data Transfer

SAI

Data Redirect

Data Redirect

Concordance

{jmb, ehm}@cs.stir.ac.uk

72