Psychology - Stress

• STIMULUS: event or situation, source of stress
• RESPONSE: physiological response
• INTERACTION: relation between person and situation

Selye (1956) stress is the non-specific response of the body to any demand      made upon it.

some symptoms: Loss of Appetite 

   Loss of weight/strength

           Loss of ambition

           Facial expression

selye said the non-specific response to stress reflected the general adaptation syndrome (GAS) 

• CNS (Central Nervous system)

coordinates all bodily functions and behaviour.

• connected to brain and spinal cord
• BRAIN: hypothalamus - important

       regulates sympathetic branch of the ANS

       controls pituitary gland (part of endocrine system)

       2 parts: posterior and anterior

• PNS (Peripheral Nervous System) 

Sends information to CNS from senses

Sends information from CNS to produce behaviour

• Somatic Nervous System (SNS)
• Autonomic Nervous systerm (ANS) 

- regulates internal body processes

- links viscera (organs) annd CNS 

• Sympathetic Branch - prepares body for activity

        'fight or flight response' Cannon (1927)

------> ENDOCRINE (hormonal) SYSTEM

• Parasympathetic Branch - predominates when relaxed and stores energy

• Hormones: chemical messengers which control bodily state and behaviour

• Pituitary ('master gland') releases hormones which control secretion of    other hormones from other glands.

• Adrenal Glands     comprise of: Adrenal Medulla (inner)

      Adrenal Cortex (outer)

ALARM REACTION

• shock phase: resistance to stressor reduced

         blood pressure and muscle tension drop

• countershock phase: hypothalamus activates sympathetic branch of ANS

   adrenal medulla secretes adrenaline and noradrenaline

   (catecholomines)

• catacholomines: mimic activity of sympathetic branch

    maintain increased levels of physiological activity

    ('fight or flight response' canon 1927)

RESISTANCE

stressor not removed

sympathetic activity decreases

output of adrenal cortex increases 

>> more ACTH from anterior pituitary (controlled by hypothalamus)

ACTH makes adremal cortex release corticosteroids

regulate blood glucose levels >> resist stress

(contributes to 'fight or flight response' cannon 1927)

EXHAUSTION

once ACTH is in the bloodstream, it prevents production of more

if stressor is removed, blood sugar levels return to normal

stressor continues.. pituitary-adrenal excitation continues

• resources become depleted
• adrenals can't function properly
• blood glucose levels drop
• psychophysiological disorders develop

• helps account for physiology of stress

• not all stressors produce the same physiological pattern

• research into GAS involved mainly rats

• selye ignored psychological aspects of stress (must be percieved as a stressor for physiological response to occur)

Sympathetic branch produces generalised arousal - FOFR

ancestors in life-threatening situations 

today - stressors are not life-threatening.. more psychological

used to be adaptive, today it is maladaptive

• chronic stress repeated episodes of increased BP/heart rate - thrombosis
• adrenaline/noradrenaline add to cholesterol levels = clots 
• raised heart rate more rapid cholesterol build up, high BP 

Aim: find role of non-physiological factors in CHD. (role of individual differences) 

Method: 3000 American men, aged 39 - 59

       Over 8 years (all healthy when study began) 

assessed by structured interview and self-assessment test (multiple choice)

classed as either: Type A Behaviour (TAB)

            Type B (non-Type A) Behaviour  (TBB)

TAB: Chronic time urgency, competitive, generalized hostility.

always in a hurry, cant queue, multitask, need to be admired

TBB: Self-confident, relaxed and easy-going, less hostile, not driven for perfection

Results: Type A more likely to develop CHD than Type B (twice as likely)

Conclusions: Personality can affect likelihood of CHD 

Personality can be counted as a 'risk factor' 

Psychological factors have physiological effects

Stressors aren't harmful in themselves its the response that is potentially dangerous

Evaluation: cannot generalize results to women

    repeats were not in keeping with original results

    TAB assessed after a heart attack does not predict future attacks     (Penny 1996)

Immune response is reduced.

more likely to become ill when 'under stress' 

'immunosuppressive effects of stress' 

due to continuous production of corticosteroids

(interferes with production of antibodies)

Riley (1981) Mice on a turntable

    After 5 hours, reduce in lymphocyte count

    = suppressed immune response

Riley also tested the effects of stress on tumors.

mice on turntable for 10 minutes an hour for 3 days developed tumors

mice on no rotations did not.

Aim: wanted to study the 'competance' of the immune system in people facing stressful situations

(medical students facing important exams) 

Hypothesis: immunosuppression would be reduced by stress

     (measured killer cell activity)

Method: 75 medical students (49M, 26F)

Took blood samples 1 month before final exams and day of first exam

(after paper was sat) 

Leucocyte activity measured

Results: killer cell activity greatly reduced in second sample

       given questionnaires to assess other potential sources of stress

       most lonely/suffer from depression etc. = lowest killer cell activity

Conclusions: stress is associated with immune function 

immunosuppressive effects of stress increased depending on stressor

Evaluation: Natural experiment

     Participants compared to themselves

     May not only be the stressors affecting immunity

Aim: to construct an instrument for measuring stress

defined stress as amount of change

Method: examined medical records of 5000 patients

list of 43 life events

came up with a numerical value to judge stress for each event 

(using 100 judges and the mean) 

add up value for an individual's stresses in 12 months

= total number of LCU's (life-changing units) 

Results: only 6 events deemed more stressful than marriage people with a high LCU were more likely to develop an illness

over 300 = 80% chance 

Conclusions: stress can be measured objectively by LCU score

this can predict chances of illness

stress makes us ill

Evaluation: SRRS assumes all change is stressful

     May be confusing change with negativity

     later, when asked to define change as 'controllable' and 'uncontrollable', only the latter correlated with illness. Brown (1986)

Hassles: irritating things in everyday life

annoying practical problems

eg. traffic jams, losing things, bad weather, arguments

Uplifts: positive experiences 

     eg. joy from love, relief, good news, good night's sleep

Kanner et al.  its the cumulative impact of these day-to-day problems that may prove detrimental to health

Brady (1958) 'executive monkeys'

monkeys placed in 'restraining chairs' and conditioned to push a lever

got an electric shock every 20 seconds unless they pushed the lever

many monkeys died from ulcers (must be caused by electric shock or stress)

restrained monkey, no shock, no adverse effect

Follow-up study measured relationship between stress and ulcers 

in pairs - one could not control shocks, other could by pressing lever

lever - ulcers

no lever - fine

stress = illness

Aim: relationship between low control in the job and CHD

Method: all M and F civil servants between 35 and 55 in 20 London stations

sent introductory letter and screening questionnaire

offered screening examination for cardiovascular disease

employment grades grouped into 3 categories

(administrators, executive officers and clerical/office staff)

job-control measured by initial questionnaire

Aim: relationship between low control in the job and CHD

Method: all M and F civil servants between 35 and 55 in 20 London stations

sent introductory letter and screening questionnaire

offered screening examination for cardiovascular disease

employment grades grouped into 3 categories

(administrators, executive officers and clerical/office staff)

job-control measured by initial questionnaire

Results: age was taken into account

       lowest grades (office staff etc) was 3 times more likely to develop CHD

Conclusions:  Low control at work is a large contributor to developing CHD

Evaluation: 

• suggests too little stress can damage your health - against common sense (counter-intuitive)
• people compared to themselves - not affected by individual differences
• large sample size
• based on self-report in the questionnaire
• may not be typical of non-British civil servants

TAB:

Individual perception defines what a stressor is

must take psychological factors into account

eg. personality

TAB: way of reacting to life

greater chance of CHD (friedman and rosenman)

hostility, anger, multitask, hurry, ambition, strive to perfection

does not cause CHD

Type C:

Cancer prone

difficulty expressing emotions, tend to suppress or inhibit emotions (especially negative ones) 

Influence progression of cancer and survival time (weinman 1995) 

Hardiness: 

protective factor - ability to resist stress 

committed - meaningfulness, involved in whatever they do

challenge - regard change as normal or an opportunity

control - believe what they do makes a difference 

high internal locus of control (Rotter 1966)

Formal - intentionally used by professionals to reduce stress levels

psychotherapeutic drugs, biofeedback, cognitive behavioural therapy

increasing hardiness

Informal - what we do spontaneously on a day to day basis

coping strategies/mechanisms

Psychotherapeutic Drugs act directly on ANS

commonly used for chronic stress

reduce physiological effects of stress

may cause side-effects (drowsiness, lethargy)

over time have to increase dose due to tolerance

Cognitive Behaviour Therapy (CBT) 

Stress Innoculation Training (SIT)

cognitive restructuring - changing the way people think about their lives 

changing emotional responses and behaviour

(like a vaccine)

Biofeedback - patients shown information about BP, heartrate etc 

(autonomic functions)

can then learn to regulate them voluntarily 

(taught meditation and muscle relaxation) 

requires specialist equipment 

only treats symptoms of stress not reaction to stressor or stressor itself

1. cognitive preparation -  talk about how they deal with stressors

how successful these strategies are

common response - negative statements

2. skill acquisition and rehearsal - taught coping techniques

    preparation statements

3. application - guided through threatening situations

  not role-plays

  gradually more threatening 

(Kobasa) 3 ways:

1. Teaching - to identify signs of stress 

2. Reconstructing stressful situations - make a realistic assessment of      stressor

3. compensation through self-improvement - bounce back after going wrong through positive experience of stressors

maladaptive and adaptive

maladaptive - failing to adjust properly

      experiencing misery as a result

      emotional and avoidance coping styles

• feeling overpowered and helpless, hoping it will all go away, taking frustration out on others, pretending nothing is the matter when asked

adaptive - appropriate adjustment

 gaining from the experience

 detached and rational coping styles

• don't see the problem as a threat, taking action to change things, keeping a sense of humor, take one step at a time using logic

Cohen and Lazarus' (1979) 5 Categories of Coping

1. Direct action response: manipulate situation

2. Information seeking: try to understand situation, predict future events

3. Inhibition of action: do nothing if stressor seems temporary

4. Intrapsychic coping: reassess situation 

5. Turning to others

Lazarus and Folkman's (1984) Problem-Focused Coping and Emotion-Focused Coping

Problem-focused coping- direct action to reduce problem

Emotion-focused coping- reduce negative emotions