Stress

Sympathetic Adrenal Medullary (SAM) Pathaway:

Stressor--> Hypothalamus--> Sympathetic nervous system--> Adrenal medulla--> Adrenaline and noradrenaline--> Fight or flight reaction.

Hypothatlamus Pituatary Adrenal (HPA) Pathway:

Stressor--> CRF--> ACTH--> Adrenal cortex--> Corticosteriods e.g. cortisol--> Immumosuppression.

Procedure and findings:

• Studied first year medical students.
• 49 males and 26 females.
• Blood taken from 1 month before exams and on first day of exams.
• Given questionnaire on life events and loneliness/isolation, psychiatric symptoms.
• NK cell activity reduced between two samples.
• NK cell particularly weak in those students reporting loneliness, stressful life events or psychiatric symptoms.

Evaluation:

• High ecological validity - brief naturalistic stressors.
• Limited sample ---> lacks population validity.
• Direct measure of immune system e.g. NK cells which are part of our immunity.
• Supported by other studies.

Procedure and findings:

• Natural experiment, where the IV was if you were a carer or non carer.
• Matched pairs design.
• Wound 3.5mm below elbow - punch biopsy.
• All received exactly the same treatment for the wound.
• Carers on average took 9 days longer to heal, suggesting stress of being a carer can interfere with wound healing which is an indirect measure of the immune system.

Evaluation:

• Practical applications e.g. medical profession.

Procedure and findings:

• Participants given questionnaire asking about; number of stressful events in past year, ability to cope, negative emotions.
• Participants were exposed to common cold.
• 82% became infected with virus.
• Participants were assessed 7 days later.
• A positive relationship between stress index and cold symptoms.

Procedure and Findings:

• Used meta-analysis.
• Acute limited time stressors e.g. doing a speech - upregulation of natural immunity e.g. NK cell activity.
• Brief naturalistic stressors e.g. taking a test - this study found no effect of these on immune function.
• Chronic stressors e.g. being a carer - down regulation of specific and acquired immunity (global immunity), these showed the most consistent results.

ALL THESE STUDIES HAVE A REDUCTIONIST METHODOLOGY E.G. STRESS IS REDUCED TO A SIMPLE MEASURABLE FACTOR SUCH AS TAKING EXAMS. ALSO THE IMMUNE SYSTEM IS MADE UP OF MANY DIFFERENT FACTORS E.G. NATURAL, ACQUIRED, T CELLS AND B CELLS. BUT SUCH STUDIES REDUCE THE IMMUNE SYSTEM, TO A SIMPLE MEASURABLE VARIABLE SUCH AS NK CELL ACTIVITY. 

LCU - Life Changing Unit.

SSRS - Social Readjustment Rating Scale.

Life change - an event in life requiring a major change in some aspect of life. Sometimes they are termed critical life changes as they have a massive impact e.g. death of a spouse.

Procedure and findings:

• 43 life events were taken from 5000 patient records.
• 400 participlant scored the life events in terms of the readjustment needed; marriage = 50.
• Scored for individual life evens were totalled and averageed to produce a life change unit for each event. 
• Score over 300 = 80% chance of developing an illness. May become a more serious health risk.
• Between 150 and 300 = 50% risk.

Evaluation:

• Sample was androcentric and ethnocentic. 
• Provided important evidence which could lead to important advice given to people going through the changes.
• Life events are culturally biased as they are based on Western experiences.
• Validity and realiability of people's memory of past events has been questioned.

Daily hassles - minor events that arise through the course of the day that cause stress.

Procedure and findings :

• Used questionaire on hassles, uplifts, life events, general health and energy levels.
• Once a month for a year.
• Hassles significantly correlated with impaired health. Uplifts little effects and no effects of life events during the study.
• Daily hassles are associated with changes to health status.

Procedure and findings:

• Claimed De Longis' study had put too much emphasis on memory because questionaires were given to participants monthly.
• Stone argued that this may cause forgetting of daily hassles.
• Stone used patients with respiratory illness.
• Asked them about 100 events 10 days leading up to illness.
• Found they had more hassles and less uplifts than a control group.

• Daily hassles accumulate over the course of the day and therefore provide more significant source of stress than life changes.
• Severe life changes may make participants more susceptible to daily hassles.
• Participants may not correctly remember the hassles they have experienced (counteract by participant keeping journals).
• Use of self-report questionaires; participants may lie; also social desirability bias.
• Research is correlational so we cannot draw casual conclusions.

Practical applications: 

• Improve workplace.
• Increase productivity.
• Reduce days off sick.

Factors:

• Environmental e.g. heat, noise, crowded.
• Lack of control.
• Work overload.
• Effort reward imbalance.

Ways to reduce stress:

• Suggestion box - control.
• Work at your own pace - control.
• Reward system.

Procedure and findings:

• Used 10 finishers with repetitive and high responsibility job and 10 cleaners.
• Stress-related hormones in urine samples were recorded on work and rest days.
• Stress-related illness and amount of days off from work recorded.
• Finishers had higher stress hormone levels than cleaners, finishers had higher stress hormone levels on work days than rest days and finishers had more stress-related illnesses and more days off work.
• Work stressors, like repetitiveness and higher levels of responsibility = long term physiological arousal. Leading to stress-related illness and absenteeism.

Evaluation:

• Natural experiment - IV not manipulated by researcher.
• Low control - individual differences could effect experiment, counteract with matched pairs design.
• Practical applications.

Procedure and findings:

• Longitudinal study (5 years).
• Over 10,000 civil servants.
• Low job control and high demand meant they were 4 times more likely to develop CHD.

Evaluation:

• Self report questionnaire - could underestimate risk factors.
• The sample were government civil servants so generalisability is a problem.
• Correlational - no control over job variable, maybe people were prone to stress seek out such jobs.

Procedure and findings:

• Tested effectiveness of beta-blockers against stage fright in musicians.
• 34 singing students were given different amounts of a beta-blocker or placebo during end of term examinations.
• Low doses were found to improve performance minimally, high doses hindered performance significantly.
• Does not offer much support for the use of beta-blockers addressing performance anxiety.

Procedure and findings:

• Assessed personality types of over 3500 Californian men aged 39 to 59, for 8.5 years.
• Participants were asked questions on impatience, competitiveness, motivation for success, frustration at goals being hindered and their feelings towards being under pressure.
• High scores = Type A and low scores = Type B.
• Observed to assess personality types and health status, interviewer purposely interrupted interviewee.
• Found 257 men had developed CHD during 8.5 years, 70% of those had been classified as type A.
• Type As were found to have higher levels of adrenaline, nor adrenaline and cholesterol.
• Type As were strongly linked to CHD, type A behaviour pattern increased the individuals experience of stress, which increased physiological activity therefore increased vulnerability to stress-related illness.

Hardy personality - healthy personality type characterised by challenge, commitment and control.

Challenge - when a person sees life changes as obstacles or opportunities that they can overcome.

Commitment - when a person is aware of their own purpose and sense of involvement in the world and of their own life.

Control - when a person feels that they are in control of everything that happens in their lives.

• Correlational study - cannot determine cause and effect e.g. does the stress cause CHD or CHD cause stress.
• Practical applications - treatment programmes have been designed which can reduce chances of getting a second heart attack or train people to be less type A i.e. made people aware of the dangers so that they could change their lifestyle.
• Too broad - identified as a toxic factor rather than type A as a whole. Hostility is the toxic factor.
• Control - lack of control such as whether people have a healthy diet, smoke etc.

Procedure and findings:

• Studied male business executives high in stressful events. The three hardiness components, i.e. challenge, commitment and control, were assessed.
• Compared against illness scores both at the time and a year later.
• On both occasions probability of illness was lower for hardy individuals than non hardy individuals.

Procedures and findings:

• Studied highly stressed male business executives who were divided into two groups i.e. those who became sick after stressful life events and those who didn't.
• Found on average those who didn't suffer from illness were more hardy than those who did.

Evaluation:

• Practical applications - hardiness will result in improved health and decreased blood pressure.
• Androcentric research.
• Correlational evidence.

Benzodiazepines - increase neurotransmitter GABA, reduces serotonin which makes you feel more relaxed. Readily available from doctor, but should only be used in the short term as tolerance is build. Side effects include drowsiness, addiction and dependency.

Beta-blockers - blocks physical symptoms of stress by reducing sympathetic arousal, can be used in the long term as they do not have their effect on the brain.

Stress Innoculation Therapy:

• Conceptualisation - therapist and client work together to discuss what in the client's life makes them stressed.
• Skills acquisition - therapist teaches client skills, such as deep breathing, that the client can use when they are feeling stressed.
• Application - client used the skills that they have learnt in real life situations.

Procedure and findings:

• Assessed BZ usage as treatment for 75 patients with social-anxiety disorder.
• Patients randomly assigned to drug or placebo group for 10 weeks.
• Drug treatment was found to have an early and sustained positive effect, 78% of patients improved.
• Only 20% in placebo group improved.
• Patients using BZs reported side effects e.g. unsteadiness, forgetfulness and loss of concentration.
• Two year follow up found significant advantage in function among those treated with BZ drugs than a placebo, suggesting BZs to be effective in short and long term.