STRESS REVISION! Flashcards
STRESS AND ILLNESS
Direct cause of stress/illness?
Cortisol produced by the HPA (hypothalamic-pituitary-adrenal system) inhibits production of immune cells / lymphocytes
Indirect cause of stress/illness??
Stress influences lifestyle behaviours e.g. smoking / drinking alcohol
Negative functioning on immune system
Kiecolt-Glaser - study on 75 medical students
Took blood samples / self-report questionnaires of psychological symptoms in a low-period of stress before exams and a period of high-stress during exams.
Found: a decrease in NK and T killer cells (which fight off viral infections??) between blood samples - negative.
SHOWS EVIDENCE OF AN IMMUNOSUPPRESSIVE RESPONSE TO A SHARED STRESSOR
Kiecolt-Glaser’s study on caregivers & THE EFFECTS OF CHRONIC STRESS
Caregivers looking after elderly relative with alzheimers - compared with a MATCHED control group not caregivers.
Found: higher levels of depression in caregivers (32% compared w 6% of control group)
After 13 months, found that the caregivers produced more antibodies to the Epstein-Barr virus. more susceptible to getting ill.
EVALUATION:
LIMIT 1
Assumption that stress negatively impacts immune system challenged! Research: stress can have immuno-enhancing effects!!
Dharbar’s rats - subjected to mild stressors e.g. mild shock - major immune response! lymphocytes flooded bloodstream / body tissues in preparation for physical damage - beneficial.
Therefore, ACUTE AND CHRONIC STRESSORS DO NOT AFFECT THE BODY IN THE SAME WAY
THEREFORE RELATIONSHIP BETWEEN STRESS / ILLNESS IS COMPLEX, NOT FULLY UNDERSTOOD
EVALUATION:
LIMIT 2
Limited research: focuses on short-term, acute stressors
e.g. mild shocks / unfair money distribution??
LACK EXTERNAL VALIDITY
NO / LITTLE INSIGHT INTO THE EFFECTS OF LONG-TERM, CHRONIC STRESSORS. Even lab studies on longer-term chronic stressors use artificial stressors e.g. noises/ electric shocks, so lack external validity
EVALUATION:
STRENGTH 1:
RESEARCH SHOWS LINK BETWEEN IMMUNOSUPPRESSION AND CANCER
PEREIRA’s Study on HIV-positive women. Those who experienced stressful life events in the past year had an increased chance of developing cervical lesions than those who had not.
THEREFORE THIS IMPLIES THAT THE EFFECTS OF STRESS ON HEALTH HAVE WIDER, MORE DIRECT EFFECTS THAN PREVIOUS RESEARCH FOCUSING ON CVDs HAS SUGGESTED
EVALUATION:
STRENGTH
RESEARCH INTO ILLNESS AND STRESS HAS REAL LIFE APPLICATIONS - wider implications
Dharbar’s study on rats - in the future, low doses of stress hormone could be given to patients before surgery to increase their chances of a full recovery
Kiecolt-Glaser’s study on students during exam period - students who took relaxation programmes seriously during exam period had better immune functioning than those who did not
RESEARCH WITH R.L.A HAVE INCREASED INTERNAL VALIDITY AS THESE APPLICATIONS CONFIRM THE RELEVANCE OF CONCEPTS UNDERLYING THEM E.G. EFFECTS OF STRESS ON THE IMMUNE SYSTEM
Stress associated with CVDS
e.g. cardiovascular disorders - heart attacks / stroke (blocked blood vessels in the brain) / CHD (Coronary heart disease)
Some evidence shows that stress has immediate effects on CVDs (acute) as well as longer-term effects (chronic)
CVD research - YUSUF
Yusuf’s INTERHEARTS STUDY compared 15000 individuals who had experienced a heart attack (myocardial infarction) with a control group who had not
FOUND: SEVERAL CHRONIC STRESSORS HAD A STRONG LINK TO MI - found ROLE OF STRESS GREATER THAN OBESITY, but behind smoking and cholesterol.
Chronic stressors e.g. workplace stressors - heart attack
CVD RESEARCH
WILBERT-LAMPEN - retrospective study on heart attacks related to the 1996 world cup in Germany
Found: 2.66 x more incidences of heart attacks in football fans who experienced sudden emotional arousal while watching the game (acute stressor) compared with a control period. MORE THAN DOUBLED PARTICIPANTS’ RISK OF SUFFERING A CARDIOVASCULAR EVENT!