Specification:
1. The physiology of stress, including general adaptation syndrome, the hypothalamic pituitary-
adrenal system, the sympathomedullary pathway and the role of cortisol.
2. The role of stress in illness, including reference to immunosuppression and cardiovascular
disorders.
3. Sources of stress: life changes and daily hassles. Workplace stress, including the effects of
workload and control.
4. Measuring stress: self-report scales (Social Readjustment Ratings Scale and Hassles and
Uplifts Scale) and physiological measures, including skin conductance response.
5. Individual differences in stress: personality types A, B and C and associated behaviours;
hardiness, including commitment, challenge, and control.
6. Managing and coping with stress: drug therapy (benzodiazepines, beta blockers), stress
inoculation therapy and biofeedback. Gender differences in coping with stress. The role of
social support in coping with stress; types of social support, including instrumental,
emotional and esteem support.
1. The physiology of stress, including general adaptation syndrome, the hypothalamic
pituitary-adrenal system, the sympathomedullary pathway and the role of cortisol.
AO1 – response to short-term stressors
The sympathomedullary pathway (SAM or SMA pathway)
S – Sympathetic nervous system (branch of autonomic nervous system) is alerted by the
hypothalamus as soon as a stressor is perceived.
M – adrenal medulla. A nerve impulse is sent to the adrenal medulla (middle of the adrenal
glands). Medulla releases adrenaline + noradrenaline into the blood.
A – adrenaline + noradrenaline circulate through the body, causing increased heart rate,
blood pressure, etc so animal is ready to deal with stressor.
AO1 – response to long-term stressors
The hypothalamic pituitary adrenal system (HPA axis).
H – hypothalamus releases CRH (hormone) into the blood
P – pituitary gland. CRH causes the pituitary gland to produce + release ACTH into blood.
A – adrenal cortex. ACTH stimulates the adrenal cortex to release cortisol into the blood.
Cortisol further stimulates the breakdown of glycogen into glucose (for increased energy in
respiration), causes lower sensitivity to pain + supresses immune system so that the
maximum amount of energy is directed to dealing with the threat.
AO1 – General Adaptation Syndrome
Established by Selye
Describes physiological reactions that occur in response to stress in 3 stages:
1. Alarm reaction – threat or stressor is recognised + response made. Hypothalamus
signals the sympathetic nervous system, which activates + stimulates the adrenal
medulla to secrete adrenaline + noradrenaline, triggering fight or flight response.
2. Resistance stage – if stressor continues, body recovers from initial alarm + adapts to the
demands of the environment while resources (biochemical substances constantly
manufactured in the body – sugars, neurotransmitters, hormones) are being depleted.
, 3. Exhaustion stage – if stressor still persists, body’s systems can no longer maintain
normal functioning, possibly resulting in stress-related illnesses such as ulcers,
depression, or cardiovascular problems.
AO3 – short- + long-term stress
Gender differences
- Biological research generally relies on male animals because female hormones fluctuate
with ovulation (less easy to measure + draw conclusions from) so possibly male bias.
- Taylor et al suggested that female behavioural response to stress may be more ‘tend +
befriend’. During evolutionary past, this would have involved protecting themselves +
young through nurturing (tending) + forming protective alliances with other women
(befriending).
- Studies using rats show the release of oxytocin in response to stress induces relaxation,
decreasing the fight-or-flight response.
Fight or flight response – inappropriate for modern stressors
- Physiological responses of fight or flight response are adaptive for a stress response
requiring physical activity.
- Present day stressors generally don’t require such a physical response – evolutionary
hangover.
- When stress response = repeatedly activated, problems arise e.g., increased blood
pressure can lead to physical damage in blood vessels + too much cortisol suppresses
the immune response.
The transactional model of stress
- Lazarus argued physiological stress response was not inevitable, but it depends on how
the stressor is perceived + this determines the actual response.
- Lazarus + Folkman developed a transactional model of stress in which cognitive appraisal
= key – the perceived demands on the individual + individual’s perceived ability to cope.
- Demonstrated in a study where participants watched a film depicting male circumcision
– group 1 – commentary talking about excitement of being accepted as a man vs group 2
– commentary focused on pain of procedure. Group 1 experienced less autonomic
system arousal.
AO3 – general adaptation syndrome
Based off Selye’s investigation with rats, tracking their responses to a continuing stressor
through resistance + exhaustion stages.
- Positive – harsh conditions e.g., excessive exercise or extreme heat mean study wouldn’t
have been ethical enough to carry out on humans + rats = mammals so element of
behavioural continuity with humans (similar physiology).
- Some argue too unethical to carry out on rats
- Rats lack higher cognitive abilities + are unable to communicate with humans so can’t
explain effects of stress are (Selye had to make conclusions purely based on
observation).
Might not be one response to all stressors.
- Mason replicated Selye’s procedures using 7 different stressors in monkeys + found
varied effects depending on stressor.
- E.g., extreme cold increased cortisol levels, extreme heat decreased cortisol levels +
excessive exercise didn’t change cortisol levels.
- Selye’s model possibly over-simplistic – reductionist to suggest one universal response.
- Higher validity/ more ground to be applied to humans because use of monkeys.
Positive ethical implications