Role of Stress in Illness: Studies
Psychology: AQA A Level, topic 14.1.3
Krantz et al (1991) & Brady et al (1958)
Krantz et al (1991) investigated the effects of stress on cardiovascular disorders. Brady et al (1958) investigated the effects of control and responsibility on stress
Krantz et al (1991) procedure
- Laboratory experiment.
- 39 participants were given 3 tasks of varying degrees of difficulty and stressfulness. They also had their blood pressure measured and extent to which vessels around the heart contracted (myocardial ischaemia).
Krantz et al (1991) results
- Results
- Most stressful tasks induced higher blood pressure and increased myocardial ischaemia. Conclusion
- Stress may have a direct effect on blood pressure and myocardial ischaemia, making cardiovascular disorder more likely.
Krantz et al (1991) evaluation
- Strengths
- Controlled and reliable.
- Ecological validity.
- Limitations
- Individual differences.
- Cannot show cause.
Brady et al (1958) procedure
- Laboratory experiment.
- Rhesus monkeys were yoked together in pairs and received shocks every 20 minutes in 6-hour shifts.
- The ‘executive’ monkey could control the shocks by pressing a lever. The control monkey had no control over the shock schedule.
Brady et al (1958) results
- Results
- The ‘executive’ monkeys developed stomach ulcers and died quicker than the control group of monkeys.
- Conclusion
- From this study the concept of ‘executive stress’ arose. Control and responsibility for others was seen as more stressful than being a worker with little responsibility for others.
Brady et al (1958) evaluation
- Strengths
- Controlled and reliable.
- Limitations
- Ethics.
- Cannot generalise from animals to humans.
- Monkeys allocated to ‘executive’ condition were the quickest learners, so may have been more stressed by the shocks initially and therefore more susceptible to stress related illnesses.
Test yourself on Role of Stress in Illness: Studies
What was Krantz et al's (1999) research method?
What was Brady et al (1958) procedure?