PYA2 - Stress

Stress -

The experience of a lack of fit between a person and their environment (the percieved demands of a situation are greater than a persons percieved ability to cope.

Stressors -

Any event that causes a stress reaction in the body.

Stage 1 : ALARM - Drop in blood pressure, muscle tension etc ..

Stage 2: RESISTANCE - Chemical production

Stage 3: EXHAUSTION - Body in need of recovery.

Non- specific physiological response to a variety of stressful situations.

(How body copes with extreme sttress - several symptoms so a syndrome!)

REMEMBER A.R.E !!!!

Criticisms

:) - Influential - stress can lead to illness/Adrenaline is needed to respond to stressors

:( - use of non - human animals/Resources do not become depleated even under extreme stress

* Hypothalamus *

(releases CRH)

* Pituaitary Gland*

(releases ACTH)

* Adrenal Gland *

(releases stress hormones)

*Increase energy release, suppresses inflammatory response and suppresses immune response*

* Hypothalamus *

* Sympathetic Nervous System *

* Adrenal Medulla *

* Increase cardiovascular response, increas respiration, increase perspiration, sends blood to muscles, stimulates mental activity and increases metabolism *

* Blood pressure (inflated arm band)

* Breathing (Tubes around chest)

* Heart Rate (ECG)

* Sweating

* Hormone Levels (Blood Urine)

A - To see if stress could increase myocardial ischemia and see if CHD patients reacxted differntly to non CHD patients.

P - 39 patients/12 controls - 3 midly stressful tasks (Stroop, publis speaking and maths test). Blood pressure measured and how much coronary blood vessels contacted (high, med and low ischemia)

F - Some CHD patients showed high myocardial ischemia and blood pressure, some had mild ischemia and moderate increase in blood pressure and the conrtrol group showed lowest levels of BP and ischemia.

C - Support link between stressful tasks and physiological activity that could damage the CVD. Not all CHD patients reacted in same way therfore individual differences in respinsiveness.

C - Ethical issues - giving mild stress to patients/ particiapnts gave informed consent/ stress no more than everyday life.

Validity- No controls to compare behaviour when stressed and not stressed so raised levels of ischemia may not be just due to stress.

A - To demonstrate the direct effects of stress on the immune system, by looking at how quickly wounds heal.

P - Matched participants. volunteer sample (newspaper advert). 13 carers aged 47-81 =experimental group. Control group - 13 particpants (matched for age and income not marital status). All given a wound just below elbow, dressed and treated by nurse. Also levels of cytokines measured. percieved stress scale to fill out.

F -Wound helaing on average nine days (24%) longer in carers than control group. Cytokine levels lower in carers then control (lower immunity) Carers more stressed on percieved stress scale.

C - Supports view that chronic stress depresses functiong of immune system. lower cytokine levels show that stress lowers immune response directly.

C - :) Applications - Important implications for treating infections/ reduce stress for quicker recovery.

:( Sample Bias - Matching participants in exact ( social support, smoking, marital status) not taken into consideration - could have effected the results.

A - Using SRRS scale to see if number of life events experienced by normal people would be positive correlated with illness

P - Opportunity Sample -military version of SRRS given to 2,700 men aboard 3 US Navy crusiers. Filled in questionnare before sailing - all life events in last 6 months. Illness scale calculated on number, type and severity of illness recoredon duty (7 months)

F - LCU and illness scores showed a positive correlation of +0.118 - weak but significant because of large sample size

C - Supports a link between life changes/ events and physical illness. The link may be stress because life changes cause stress and stress causes illness.

C - Unreliable data - may forgotten life change's or repressed them.

A - Test job strain model.. work creates stress and illness on 2 ways ... 1) High Demand and 2) Low Control

P - London civil servants invited to take part 7,372 agreed to answer a questionnaire and checked for CVD. Reassessed 5 years later. Social supoort taken into consideration.

F - Higher grad workers fewest CV problems. Lowest grades had less control and porest social support. CVD could be explained because of risk factors like smoking and obesity.

C - Low control linked to higher stress and CVD. High demand not linked to stress or illness. Does not fully supoort strain model.

C -Socioeconomic status may bea bigger factor than job in causing CVD. Biased sample - all civil servants. Caplan 75, ambitious indivduals more affected by work place stressors (civil servants maybe more ambitious, living in city.

Type A - Aggressive, ambitious, competitive drive, chronic stress of time urgency. Raised blood pressure and levels of stress hormones. more susepctiable to CHD and cancer.

Type B - Lacking type A characteristics. Opposite to how type A deal with stress.

Type C - Suppress emotions, inssertive, liekable and generally helpful to others. Cope with stress in a way that ignores their needs.

Type D - Gloomy, socially inept and worriers. Greater risk of heart attack

Hardiness -

* Control - feel in control of their lives

* Commitment - involved in world around them

* Challenge - see life changes as challenges

Drug therapy

- Benzodiazephines (Bz's) - reduce nrevous system activity. Serotonin reduced - slows down activity of neurons.

- Beta blockers reduce ANS activity

Reduce blood pressure and arousal less stress

:) High efficancy/ work quickly/ low toxicity/ increased survival/ easy to take

:( Addictive/ side effects e.g. dry mouth/diarrhoea/seizures etc..

Biofeedback

Person learns to exhert voluntary control over involuntary behaviours. it involves 4 processes.

1. Feedback

2. Relaxation

3. Operant Conditioning

4. Transfer

Hardiness training

Kobasa and Maddi (1977)

1.Focusing

2. Reliving stress encounters

3. Self improvement

Both treat the problem not the symptoms

Stress Inoculation Training

Meichenbraum (1985) - cognitive behavioural therapy.

1. Conceptulisation

2. Skills training and practice

3. Real life application and follow through

:) it works/combines cognitive and behavioural therapy

:( Complex/time consuming