Biological-Stress Flashcards
Define stress
The subjective experience of a lack of fit between a person and their environment. (I.e. where the perceived demands of a situation are greater than the person’s perceived ability to cope.
Describe the acute stress response.
The SAM (Sympathomedullary Pathway) Is activated: Short lived stressors arouse the sympathetic branch of the autonomic nervous system which arouses the person for fight or flight. At the same time the adrenal medulla releases adrenaline into the bloodstream boosting the supply of glucose and oxygen to the brain. This leads to physiological changes: •Increased Heart Rate •Increased Blood Pressure •Increased Breathing Rate •Mouth Becomes Dry •Digestion Stops
Describe the chronic stress response
The pituitary adrenal system involves the hypothalamus which leads to the production of CRF. This causes the pituitary gland to release ACTH into the bloodstream which travels to the adrenal cortex which releases cortisol into the bloodstream. Cortisol increases the amount of glucose in the blood stream.
Effects of acute stress on the immune system:
Kielcolt-Glaser et al. (1984)
Aim: To find out if exam stress affects the immune system
Method: Natural experiment
IV= time before the exam 1 month before (high stress), during the exam (high stress)
DV= NK cells activity
The students were also given questionnaires to assess psychological variables such as life events.
Sample: 75 American medical students
Findings: NK cell activity was lower during the exams.
Conclusion: Examination stress reduced the immune function, potentially leaving the individual vulnerable to illness.
Evaluate Kielcolt-Glaser et al. (1984)
Sample:
American Ps: Results cannot be generalised as different cultures have different lifestyle factors which can affect the immune system i.e. diet.
Medical students: Stronger immune system as in daily contact with patients carrying new germs, young Ps (students) therefore stronger immune system than younger and older people.
Natural experiment:
Lack of control of extraneous variables (give an example and explain how it could affect the immune system).
Other possible points:
The measure of the immune system is very objective (NK cells activity) and scientific.
Effects of chronic stress on the immune system
Kiecolt- Glaser et al. (1995)
•Chronic stress reduces the ability of the immune system to heal in women caring for relatives with Alzheimer’s Disease.
Matched pairs design
Wounds healed 9 days later than control groups
Assessed using photographs and hydrogen peroxide
What are life events/ life changes and why do they cause stress?
- Major life events are significant events that lead to life changes. These require a significant adjustment in various aspects of a person’s life and therefore cause stress. E.g. bereavement, divorce, marriage.
- These take up our “Psychic Energy”
- Constantly having to think, and use up energy, leaves us feeling exhausted and less able to cope with other parts of our lives.
- The bigger the change, the more adjustment has to be made; therefore the more energy has to be used.
What is the Social Readjustment Rating Scale (SRRS)?
The Social Readjustment Rating Scale was developed by Homes and Rahe (1967) as a way to measure life changes.
43 life events were taken from 5000 patient records.
400 Ps scored the life events in terms of the readjustment needed; marriage = 50.
Scores for individual life events were totalled and averaged to produce a life change unit (LCU) for each event.
A score of over 150 LCU is viewed as a life crisis and increases the chance of stress-related illness by 30%
A score of over 300 LCU is a major crisis and increases the risk to 50%.
Study supporting the effects of life events on health.
Rahe et al.(1970)
Procedure: This was a correlational study. Using 2700 members of the US navy. All life events of previous 6 months recorded – before a tour of duty-using an adapted version of the SRRS. During the tour of duty – illness score calculated.
Findings: A positive correlation (+0.118) between the life events score and the illness score.
Conclusion: Experiencing more life changing events increases the chance of stress related illness. However the correlation was weak so other factors are involved.
Evaluate Rahe et al.(1970)
Sample:
Very large sample.
American Ps: Results cannot be generalised as different cultures have different lifestyle factors which can affect health i.e. diet..
Members of the Navy do not have the same lifestyle than most other people, for example they have less social support from family.
Correlation
Does not show cause and effect relationship between the factors, other factors could be involved (give example and link to health).
Questionnaires
Social desirability bias
Demand characteristics
Retrospective data (Ps might have forgotten some events).
Evaluate SRRS as a way to measure stress
It does not take into account individual differences and how these influence the impact of life events.
It relies on self-report questionnaires: Social desirability might influence the response (i.e. might not want to report some events: Imprisonment).
It relies on retrospective data: People might have forgotten some events.
Most of the studies done are correlational studies therefore they do not show a cause and effect relationship between the factors.
It does not take into account the everyday stressors such as traffic or meeting deadlines.
What are daily hassles and uplifts?
- Daily hassles: the irritating, frustrating, distressing demands that to some degree characterise everyday transactions with the environment.
- Daily uplifts: the opposite, the minor positive experiences of everyday life, for example, receiving a compliment at work.
What evidence is there that daily hassles affect health? (key study)
DeLongis et al (1982)
•Method: 100 participants from San Fransisco (age 45-64, well-educated with high income). Completed 4 questionnaires every month for a year. (Hassles scale, uplifts scale, life events questionnaire, health questionnaire).
•Findings: Frequency and intensity of hassles were significantly correlated with impaired overall health status and bodily symptoms. Uplifts had little effect on health. No relationships were found between life events and health during the study.
Evaluate DeLongis et al. (1982)
Sample
Well educated with a high income means they may have very different hassles to the rest of the population (e.g. not as many money hassles).
Procedure
Retrospective recall- difficult to remember hassles after a month.
SRRS and hassles questionnaires could lead to social desirability bias or ambiguous questions.
Evaluate daily hassles and uplifts as a way to measure stress.
The accumulation effect- lots of studies show that the build-up of daily hassles can lead to stress.
DeLongis et al. later added a section to their questionnaire where you could rate how hassling or uplifting a factor is.
The amplification effect- it could be the major life events/ changes that make people more vulnerable to daily hassles.
Retrospective recall- it is difficult to remember daily hassles.
Individual differences–different people find different things hassling.