Transcript Identification of Stress Placement in Speakers with and without Dysarthria

Identification of Stress
Placement in Speakers
with and without Dysarthria
Pamela Campellone
Thomas DiCicco
Rupal Patel
Background
Traditional research focus in dysarthria
due to CP: Articulation
 More recent research: Prosody
 Acoustic findings: Preserved prosodic
control at vowel & word level

Background
Are acoustic signals consistent and
reliable?
 Can humans and/or machines make use
of these signals?
 If prosody is a strength, can it be
harnessed to improve segmental clarity?

Research Questions
Can listeners identify stress within phrases
produced by speakers with dysarthria &
age-gender matched healthy controls?
 How accurate is machine classification of
prosodic contrasts?

Method

Spoken database: 12 speakers with
dysarthria (DYS) & 12 healthy controls
(HC)
5
phrases (4 monosyllabic words) produced
with stress on 1 of the 4 words or neutrally

48 monolingual speakers of American
English served as listeners
4
listeners per DYS-HC speaker pair
Listener Interface
100
98
HC Ave
% Accuracy
96
DYS Ave
94
92
90
88
86
1
A
B2
3
C
Stress Location
4
D
N5
Acoustic Predictors of Listener
Accuracy (p<0.01)
Machine Classification

HC & DYS words classified as stressed
vs. unstressed
 HC
accuracy: 98.1%
 DYS accuracy: 97.4%

Separate combinations of duration,
intensity, & F0 used to determine which
were most predictive
Accuracy by Acoustic Predictors
Predictor
Dur
Int
F0
Dur + Int
Dur + F0
Int + F0
Dur + Int + F0
HC
81.7
89.9
96.7
95.3
96.6
97.1
98.8
DYS
77.8
88.3
96.2
92.0
96.5
96.6
97.4
Conclusions
Unfamiliar listeners & machine classifier
both highly accurate
 Communicative potential of prosody

 Clinically:
scaffolding for improved intelligibility
 Application: communication aids which utilize
prosodic variation
Future Directions

Examine productions of speakers with
varying etiologies of DYS
 Differences
in acquired vs. congenital?
Assess prosodic control in more varied
speech tasks
 Design comprehensive interventions
incorporating speaker and listener
variables
