What is Health Psychology?

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Transcript What is Health Psychology?

Biology (illness) and Stress
Objectives:
Discuss physiological aspects of stress.
To what extent do biological, cognitive and sociocultural
factors influence health-related behavior?
Does Stress Cause Illness?
A. Smoking
i.
Wills (1988)  Teens
a. Stress linked to smoking
initiation in adolescence
ii. Carey, 1993  Relapse
a. Those with higher stress
more likely to relapse
iii. Gilbert & Spielberger, 1987
a. Stress reliever?
B. Alcohol
i.
Link between negative mood and alcohol
consumption
ii. Cappel & Greeley, 1987
a. People drink for its tension-releasing
properties
iii. Negative moods (internal stressor),
consequence of external stressor
C. Eating
i. Greeno & Wing, 1994 (Stress and
eating)
1. General effect model: stress changes food
intake
2. Individual difference model: predicts stress
only causes changes in eating in vulnerable
groups/ individuals
a. MOST research
ii. Stone & Brownell, 1994
1. Stress eating Paradox
a. No clear pattern
b. Sometimes stress causes overeating and
sometimes undereating
D. General Behavior Change
i.
Correlation research
1. Connection between stress and
unhealthy lifestyle
2. Connection between stress and
health problems
ii. Mtandabari, 1997 (medical
students)
1. Acute exposure to stress causes
changes in health-related behaviors
a. Minimal influence on their ability to
perform satisfactory
2. Chronic stress may have damaging
effects or long term changes in
behavior
Stress and changes in
physiology
A. Stress and illness onset
B. Stress and illness progression
C. Beliefs and physiological changes
Which factors mediate the
stress-illness link?
A.
B.
C.
D.
E.
F.
G.
Exercise
Gender
Coping styles
Life events
Type-A behavior/Type A personality
Social support
Actual/ or perceived control
Placebo and Health
Psychology
Definition of Placebo
• Inert substances which cause symptom relief
– After the sugar pill my headache went away
• Substances or actions that cause changes in
symptoms not directly attributed to specific drug
or operation
– After I had my hip operation my headache went away
• Any therapy that is deliberately used for its nonspecific psychological or physiological effects
– I had a bath and my headache went away
Problems with understanding
placebos
• What are specific/real and nonspecific/unreal effects?
– Unreal: unpredicted
– Real: it happened
– Example: ‘My headache went away after
my surgery.’
• Why are psychological factors
nonspecific?
– Example: I feel relaxed after my surgery, is
that a nonspecific effect?
• Are there placebo effects in
psychological treatments?
– Example: ‘I went to cognitive
restructuring therapy and just ended
up feeling less relaxed. Placebo or
real effect?’
• Problem Summary
– Distinction between…
• Specific and nonspecific
• Psychological and physiological
History of Placebo
• CULTURE
– Past and Today still use apparently inert
treatments
• No apparent medical (active) properties
– Faith healers & religious healers
• blood of a gladiator  Strength
• part of a dolphins penis.  Virility
• Is faith in the healer the placebo?
– OR… is there a medical substance that we
are not aware of?
Modern-day Placebos
• Recent studies
– Reduce anxiety
– Increase cognitive task
• Most effective area of study…PAIN
– Beecher, 1955
• 30% of chronic pain sufferers experience relief
– Using subjective and objective measures
– Diamond et al 1960
• Groups: Sham operation and real operation
• Results: Pain Reduction EQUAL in both groups
• Should they be taken out of the health
scenario?
Two Theories
• Non-interactive
– Examine characteristics of…
• individual
• Treatment
• health professionals and facilities
• Interactive
– Examine the individual PROCESSES,
Interaction
• Individual
• Treatment
• professional
Non-Interactive
1. Characteristics
of an
Individual
– More susceptible to placebos
– Personality
• emotional dependency
• Level of extroversion
– MOST introverted
• suggestibility
• BUT…little evidence for consistent traits
– Some traits are conflicting
2. Characteristics
of the
treatment
– Perceived seriousness, higher placebo
rate
– Example
• Surgery (perceived seriously)  Greater
Placebo Effect
– Strength of Placebo Effect
• Surgery
• Injection
• Two pills
• Characteristics of health
professional
–Higher professional status of individual
or institution has higher rate
Problems with non-interactive
theories
• Ignore the interaction
between the
characteristics
–New Theories…
•Interactive theories
Interactive Theories
•
•
•
•
•
•
Experimenter Bias
Patient Expectations
Reporting Error
Conditioning Effects
Anxiety Reduction
Physiological Theories
Interactive Theories
• Experimenter Bias (interaction between patient
and doctor)
– Patient shows change because the doctor expects
them to
• Gracely et al 1985 (double-blind)
– Groups (Patients): reduce, have no effect or increase
pain
– Doctors: pain killer or no pain killer
– Results:
• All patients given placebo
• Pain killer  reduction
• No pain killer  no reduction
– Implications
• Interaction between patient and doctor (obvious or not)
• Patient expectancies
– Ross and Olson, 1981
• All patients attributed spontaneous change to
treatment
– Why? They want to get better
– Park and Covi, 1965
• Sugar pills given to neurotics and told they were
sugar pills
• Patients showed some reduction in anxiety
– Why? Expectations?
– Motivation!! (Jensen and Karoly 1991)
• Motivation  desire to experience some change
• Expectation  belief that change would occur
• Research
– Higher motivation = higher placebo effect
•
Reporting Error
– Placebo  Latin word ‘I will please’
– Patient expect improvement, want to
please the doctor, report
inaccurately
– Therefore, (doctor or patient)
•
•
•
•
Error
Misrepresentation
Misattribution
Problems with theory
1. Not all symptoms reported are positive
2. There are objective changes with placebos
• Conditioning Effects
– Conditioning Theory
US  Treatment
UR  Recovery
OR
US  Treatment
UR  hospital, white coat
CR  recovery
– Example: people feel better before they
can digest the pill
• More effective when given in a hospital by a
doctor
• Anxiety Reduction
– Placebos decrease anxiety  helps
recovery
– Sternbach, 1978 Gate Control Theory
• Anxiety opens the gate and increases pain
• Placebos increase the level of perceived
control
• Break the anxiety-pain cycle
• Problems
– Many other effects from placebos
• Example: increased lung function in asthmatics
which is not related to anxiety
• Physiological Theories
– Levine et al. 1978
• ENDORPHINS (opiate) brains natural
pain medication
• Evidence:
– Placebos can create dependence,
withdrawal and tolerance (similar to heroine)
– Placebo effects can be blocked by giving
naloxone  blocks opiate release
• Problem
• Limited: pain reduction is not the only
consequence of placebos
Patient Expectations
Central Role…
• Patient Expectations
– Expectancy Theory
• I expect to get better
– Anxiety Theory
• I expect to improve and I am less anxious
– Reporting Error
• I attribute changes to my treatment
– Experimenter Bias
• Doctors expect me to get better
– Conditioning
• Doctors are associated with improvement
– Physiological Theory
• Changes in Endorphin release
• ALL THEORIES FEED INTO PATIENT
EXPECTATIONS
Ross and Olson (1981)
• Summary of placebo effect
– Direction of placebo effects parallels the effects
of the drug under study
– Strength of the placebo effect is proportional to
that of the active drug
– Reported side-effects of the placebo drug and
the active drug are often similar
– The time needed for both the placebo and the
active drug to become active are often similar
• Placebos work because doctor and patient
expect them to work
Horowitz et al 1990
• Foundational Research
– Coronary Drug Project (1982) & Beta-Blocker Heart Attack
Trial
• CDP  adherers had lower mortality rate
• BHAT  RCT
– Participants
• 3837 Men and Women (30-69)
• Placebo and Beta-blocker
– Data
• Psychosocial factors
– Stress, Social Isolation, Depression, Type A behavior
– Health Practices (smoking, alcohol, diet, physical activity)
• Adherence
– Poor adherers (less than 75%)
– Good adherers (more than 75%)
• Clinical characteristics
• Methodology
– Secondary data analysis (meta-analysis)
• Results
– Poor adherers were TWICE as likely to die by
1 year
• Regardless of treatment (beta-blocker or Placebo)
– Higher death rate…
•
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Not married
High life stress
High social isolation
Smokers (at baseline) and less likely to quit
• Implications
– Interaction between individuals
– Interaction between individuals and
Cognitive Dissonance
Cognitive Dissonance
• Totman (1976)
– Remove patient expectations
– Emphasize
• Justification (Justify: free from blame or
guilt)
• Dissonance (lack of harmony or
disagreement)
– Premise: Faith healing and homeopathic
medicines are still used because they
WORK
Cognitive Dissonance Theory
• Placebos work because…
– Investment by the individual
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Money
Dedication
Pain
Time
Inconvenience
– Example: winning a trip to La Palma is not as
exciting as winning a trip to Maui
Effect of Investment
•
Two processes
1. Individual needs to adjust behavior
2. Individual needs to see themselves as rational and
in control
•
Justification
–
–
•
High Justification  Low dissonance: spend money,
feel good
Low Justification  High Dissonance: spendmoney,
do not feel good
High justification results in low dissonance and
low guilt
How does justification change
symptoms?
• State of high dissonance
– Unconscious regulating mechanisms
cause physical changes that improve
health
• It is not the expectation of health it is
the need for justification
– State of cognitive dissonance
• Step 1
Premises
– Need to justify behavior
– Need to see self as rational
• Step 2
Behavior
– Invest in Treatment
• No Effect
• Step 3
Low or high Dissonance
– LOW
• Good Justification ‘I was paid’
• See self as rational
– HIGH
• Poor justification
• I chose to do it/ I am not rational
• Step 4
PLACEBO EFFECT
– Resolve Dissonance  Placebo Effect  Treatment
Works
What evidence exists for
justification?
•
Zimbardo, 1969 (experiment)
– 2 groups
1. Do not eat or drink, given $ (low dissonance)
2. Do not eat or dink, given nothing (high
dissonance)
•
Results
•
When allowed to drink, group two drank
less than group 1
•
Group 2 rationalized… I did not eat because I
was not hungry
•
Totman, 1987 (Pain Reduction)
– Experiment: Placebo (single-blind)
– Two Groups
1. Offered pain medication, $ to complete
2. Offered pain medication, no money
– Results
•
•
Group 2 experienced less pain following
WHY?
– Group 2 had high dissonance, low
justification
•
Cause physiological changes that reduced
pain
– Provided justification
– Change state of justification
So, how does it work?
• Dissonance can be resolved by the
placebo having an effect on the
individual’s health status by activating
unconscious mechanisms
Support for Theory
1. Theory can explain all placebo effects, not just
pain
2. Theory does not require expectation, but
choice
–
Explains how some individuals still see an affect
event though they do not expect to get better
3. Individual investment is needed; time, $
–
Explain treatment, individual and therapist
characteristics
Problems with Theory
• Many experiments use $, money may increase
their anxiety and therefore increase their pain
perception
• Persuasion by the experiment may create
anxiety
• Experiments in labs dealing with pain, is it real
life?
• You cannot leave expectation out completely,
otherwise why would they get involved
• Totman does not explain “unconscious
mechanisms”