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Page 1: Psycho Physiological Disorders

Psychophysiological disorders

Lecture 1

In these 2 lectures we will cover..

• definition of psychophysiological disorder

• definition and measurement of “stress”

• physiological explanations of stress response

• personaility factors affecting response to stress

• behavioural and cognitive factors affecting

response to stress

DIATHESIS-STRESS

• constitutional predisposition

triggered by

• environmental stress

PSYCHOPHYSIOLOGICAL disorders

• psychological/emotional factors which predisposeindividuals to develop physical illness

• DSM IV-R

Axis I “psychological factors affecting medicalcondition”

stress...

• Lazarus 1968

“STRESS OCCURS WHEN A SITUATION IS

APPRAISED AS EXCEEDING A PERSON’S

ADAPTIVE RESOURCES”

• ... not the situation/environment per se, but the

way the person interprets the experience

An exam situation...

...stress is produced when

• She perceives the result as an importantdeterminant of her success

• she perceives it as taxing or exceeding her abilityto prepare for and complete it successfully

• perception of the demands in relation to personalresources – and strategies available to deal withthem

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Moderators of stress

• Coping strategies (problem focused, emotion

focused)

• Social support (structural, functional - critically

NONEVALUATIVE)

• Social conflict predicts poor outcome in people

with coronary heart disease

• Social isolation confers heightened risk for

coronary heart disease

Measuring stress

• Life Change Units - Combine life event frequencyand intensity/salience

• Life event = something which demands resourcesand requires personal or social adjustment

• divorce or vacation +ve or –ve

• LCU calculated for a particular period of time byadding weighted scores of events experienced

Categories of ‘stressor’

• Life events

• Holmes & Rahe (1967): SCHEDULE OFRECENT EVENTS

• Daily Hassles?

• ... unwanted visitors, parking tickets, no milk inthe fridge.

• Population specific- daily hassles for collegestudents (Kohn et al 1990)

Traumatic stress...

• Higher death rate in

widowers within 6 months

of death of spouse

(relative to age-related

norms)

• Higher incidence of

hospital visits and 19%

increase in death rate

following Mt St Helens

eruption in 1980….

The “weak link in the chain”

• no evidence that different psychological stressors

relate to different physical disorders –

• individual’s constitutional vulnerability

determines the organ/system ‘reactive’ to stress

• stomach.. skin ..lungs ..heart

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Explaining psychophysiological

responses to stress

• Stress produces specific adverse physiological

reactions and direct damage to the body

• Stress damages the body indirectly by increasing

unhealthy behaviours

• Stress induces unhealthy cognitions and

behaviours in certain personality types, making

them vulnerable to physical illness

Physiological explanations

• emphasis on causal role of constitutional reactivity

• stem from evolutionary model –

• response to psychological threat mimics evolutionary response

to physical threat - increased b/p, muscle tension, respiratory

changes

• These have become automatic responses to psychological

stress

• often maladaptive – counterproductive – debilitating

Selye (1976)

General Adaptation syndrome

Damage may be caused by different

routes:

• inherited physiological reactivity in Autonomic

Nervous System

• specific organ vulnerability - inherited

• individual biological reactions - inherited/acquired

• immune system changes

physiological reactivity

Fewer

hippocampal

neurons

More

cortisol

secretion

Destruction of hippocampal neurons

Decreased ability to shut of cortisol secretion

Prolonged stress

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Immune system changes

Psychoneuroimmunology

Studying evidence for stress-related loweringof body’s resistance to infection/virus

“immunocompetence” = immune systemefficiency

in animals... Sklar & Anisman (1979)

• introduced cancerous growths into 2identical sets of mice

• half exposed to intermittent electric shock

• Cancerous tumours developed more rapidlyin stressed group

in humans...

• reduced efficiency of immune system

(Kiecolt-Glaser & Glaser, 1970s, 80s, 90s)

• colds and stress

• depression

• unemployment

• marital disruption

• bereavement

two possible mechanisms

• Natural killer cell: cytotoxicity significantly

diminished by induced negative self evaluations

(Strauman et al 1993)

• Efficiency of natural DNA repair systems: reduced

by stress (Glaser et al 1985)

coronary heart disease

• Most widely researchedpsychophysiological disorder

• Consider a) unhealthy behaviours and b)personality traits/cognitions in relation toCHD

Coronary heart disease

• ARTERIOSCLEROSIS - thickening and

stiffening of coronary arteries, often a

consequence of chronic hypertension

• ATHEROSCLEROSIS – thickening of coronary

arteries by deposition of cholesterol

• MYOCARDIAL INFARCTION - heart attack

- death of tissue as a result of lack of oxygen

following blockage in coronary artery

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physiological risk factors for CHD...

• Growing old

• Being male

• Smoking cigarettes

• Physical inactivity

• Having high serum

cholesterol

• Enlarged left ventricle

• Diabetes

• Having high blood

pressure

high blood pressure

• Approximately 25 million individuals have elevated

blood pressure.

• Consistent or frequent elevation = HYPERTENSION

• 92-98% of those suffering from hypertension show no

discernible organic cause

• ESSENTIAL / PRIMARY HYPERTENSIVES

• For this group, environmental stress plays a

critical role in development of hypertension

• high stress jobs + high basal blood pressure

and/or cardiovascular reactivity = essential

hypertension risk

Personality as a risk factor?

• first suggested by Friedman (1969) and Friedman

and Rosenman (1974)

• described individual with a CORONARY-

PRONE personallity...

a TYPE A individual

“any person who is aggressively involved in a

chronic incessant struggle to achieve more

and more in less and less time”

typical Type A individual...

• ..is competitive and ambitious

• ..has exaggerated sense of time urgency

• ..is aggressive and hostile

• ..is over-committed to work

• (characteristics may emerge as early as 3-4 yrs old)

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• Others not displaying these characteristics are

classified by default as Type Bs – relaxed, serene,

no sense of time urgency

Type A/B can be differentiated by

questionnaire or interview..

• Structured interview: affective/expressive styleand behaviour

Rosenthan et al (1964)

• Jenkins Activity Survey: self report

Jenkins (1968)

TRAIT vs REPONSE STYLE

• first considered as a fixed set of traits – maybe more appropriate to think of it asRESPONSE STYLE

• not invariant overt behaviour pattern –situational

• differs between populations - not allenvironments induce it

• High percentage are white middle income,middle class males

• embedded within social context ofcompetitive occupational careers in US andsimilar cultures

• in this setting may be highly adaptiveresponse style leading to desired materialgoals

Situation dependent style –

• Ratings drop radically in 50 somethings

• Bages et al (1997) – 45 University employees

• Asked participants, spouses and work supervisors

to assess Type A behaviour, anger, social support

measures in their respective environments

• Home environment: Participants andspouses agreed on all measures.

• Work environment: Participants and worksupervisors agreed on Type A assessment

• Spouses vs Work supervisors: virtually nooverlap

• situation specific Type A Behaviour Pattern