Psychology - Stress

The Sympathetic Medullary System

The body's response to acute (short term) stress:

• The hypothalamus also activates the adrenal medulla. The adrenal medulla is part of the autonomic nervous system (ANS).
• The adrenal medulla secretes the hormone adrenaline. This hormone gets the body ready for a fight or flight response. Physiological reaction includes increased heart rate.
• Adrenaline leads to the arousal of the sympathetic nervous system and reduced activity in the parasympathetic nervous system.
• Adrenaline creates changes in the body such as decreases (in digestion) and increases (sweating, increased pulse and blood pressure).
• Once the ‘threat’ is over the parasympathetic branch takes control and brings the body back into a balanced state.

Hypothalamic Pituitary-Adrenal (HPA) System

• The body's response to chronic (long term) stress.
• The hypothalamus registers the presence of a continuing stressor and stimulates the pituitary gland to release ACTH
• Which activates the adrenal cortex (outer layer of the adrenal gland).
• Which releases corticosteriods such as cortisol.
• This maintains a steady supply of energy, but also suppresses the immune system.

When we are chronically stressed, cortisol is released as a part of the pituitary adrenal system.

One effect of extra cortisol is a reduction in white blood cells, including killer T cells, which are important in fighting antigens. This means that the immune system does not work as effectively, so that we are more prone to colds, flu and other viral and bacterial illnesses.

Stress can also affect the immune system by raising blood pressure. Hypertension is a major risk factor in coronary heart disease. However, CHD may be caused by eating too much salt, drinking too much coffee or alcohol.

Stress responses also have an effect on digestive system. During stress digestion is inhibited. After stress digestive activity increases. This may affect the health of digestive system and cause ulcers. Adrenaline released during a stress response may also cause ulcers.

Kiecolt-Glaser et al (1984)

Aim: To investigate whether stress of important exams has an effect on the functioning of the immune system

Procedure:

• This was a natural experiment. The researchers took blood samples from 75 first year medical students (49 males and 26 females), all were volunteers. 
• Blood samples were taken: (a) one month before their final examinations (relatively low stress), and (b) during the examinations (high stress)
• Immune functioning was assessed by measuring T cell activity in the blood samples.
• The students were also given questionnaires to assess psychological variables such as life events and loneliness.

Findings: The blood sample taken from the first group (before the exam) contained more t-cells compared with blood samples taken during the exams.

The volunteers were also assessed using behavioral measures. On both occasions they were given questionnaires to assess psychiatric symptoms, loneliness and life events. This was because there are theories which suggest that all 3 are associated with increased levels of stress.

Kiecolt-Glaser et al found that immune responses were especially weak in those students who reported feeling most lonely, as well as those who were experiencing other stressful life events and psychiatric symptoms such as depression or anxiety.

Conclusion: Stress (of the exam) reduced the effectiveness of the immune system.

Evaluation

• This was a natural experiment which also used a real life stressful situation, so ecological validity is high.
• Measuring T cell activity is an objective way of measuring immune system functioning so demand characteristics should not be a problem.
• However, we cannot establish cause and effect (between stress and a weakened immune system).
• Also, the study does not take into account for the other factors which affect people’s lives. These can be drugs, alcohol, caffeine, nicotine, general health, diet, physical activity, sleep patterns, age and medication. It is very unlikely to gain complete control over these extraneous variables.
• Sampling bias: Participants were all students so results may not be generalisable to the general population

Life changes are infrequent, major events such as getting married, retiring, Christmas holidays etc.

Holmes and Rahe (1967) developed a questionnaire called the Social Readjustment Rating Scale (SRRS) for identifying major stressful life events. Each life event is given a score to indicate how stressful it is.

Key Study - Rahe, 1970

Aim:  to investigate whether scores on the Holmes and Rahe Social Readjustment Rating Scale (SRRS) were correlated with the subsequent onset of illness.

Procedure: 2,500 male American sailors were given the SRRS to assess how many life events they had experienced in the previous 6 months. The total score on the SRRS was recorded for each participant.

Then over the following six-month tour of duty, detailed records were kept of each sailor’s health status. The recorded number of Life Change Units were correlated with the sailors’ illness scores.

Results: There was a positive correlation of +0.0118 between Life Change scores and illness scores. Although the positive correlation was small (a perfect positive correlation would be +1.00), it did indicate that there was a meaningful relationship between Life Change Units and health (this is often referred to as a statistically significant correlation). As Life Change Units increased, so did the frequency of illness.

The researchers concluded that as Life Change Units were positively correlated with illness scores, experiencing life events increased the chances of stress-related health breakdown. As the correlation was not perfect, life events cannot be the only factor in contributing to illness.

Evaluation

• The SRRS does not consider individual difference. The scale assumes that each stressor affects people the same way. 
• The research is unethical as stress is a sensitive topic and asking participants to think about their stress on a regular basis may provoke psychological harm and in fact cause more stress.
• The data is correlational and does not prove that stress causes illness, therefore we cannot say that life changes cause illness, but only there appears to be a relationship between life changes and illness.
• The sample has a gender bias as it is based on males who may have have different ways of dealing with stress and their stressors may be different than females. This means we cannot generalize the results to females.
• Most people experience major life events very infrequently. Therefore a better measure of stress might look at the stresses and strains of daily life. These are called “daily hassles”.
• The study may lack validity due to social desirability. A with most questionnaire studies, people may lie to appear as if they are coping with their stress, or conversely, may lie to appear more stressed than they actually are to gain sympathy and attention.

Daily Hassles

Daily hassles frequent, minor, everyday events such as getting losing your keys, getting stuck in traffic, weight problems.

Daily uplifts are positive everyday experiences that are thought to counteract the effects of daily hassles e.g. good weather, talking to friends or getting enough sleep.

Daily Hassles

Daily hassles frequent, minor, everyday events such as getting losing your keys, getting stuck in traffic, weight problems.

Daily uplifts are positive everyday experiences that are thought to counteract the effects of daily hassles e.g. good weather, talking to friends or getting enough sleep.

Key Study - Kanner et al (1981)

Aim To investigating whether it is daily hassles, rather than major life events that are the most stressful. They developed a 117 item hassles scale and a 135 uplifts scale to examine the relationship between hassles and health.

Procedure: An opportunity sample of 100 American participants, including 52 women and 48 men, all white, well-educated and middle class were asked to circle the events on both scales that they had experienced the previous month and rate each according to severity (for the hassles) and frequency (for the uplifts).

Each participant was tested once a month for ten consecutive months using the two stress measures together with another two psychometric tests for psychological well-being.

Results: They found the hassles scale tended to be a more accurate predictor of stress related problems, such as anxiety and depression, than the SRRS. Uplifts had a positive effect on the stress levels of women, but not men.

Evaluation (A02)

• The research is unethical as stress is a sensitive topic and asking participants to think about their stress on a regular basis may provoke psychological harm and in fact cause more stress.
• The data is correlational and does not prove that stress causes illness, therefore we cannot say that hassles cause illness, but only there appears to be a relationship between hassles and illness.
• The sample is culturally bias/ethnocentric as it is based on 100 Americans who may have have different ways of dealing with stress and their stressors may be different than other cultures. This means we cannot generalize the results to other cultures.
• The study may lack validity due to social desirability. 

Workload

• Giving staff too much work can make them stressed because they become frustrated (when they can’t complete it). This is known as work overload. This can be quantitative, where people feel that they have too much to do or are expected to do it too quickly, or qualitative, when they find their work too difficult.
• Giving staff too little work can make them stressed because they become bored. This is known as underload.

Control

• Research has shown that lack of control at work can lead to stress. For example, no control over deadlines. People may not no control over their pace of work – e.g. if working on a production line.
• Having no control over your work rate or content; not being able to set your own priorities leads to poor physical health.

Key Study - Johansson Swedish Sawmill

Procedure: 14 employees in a Swedish sawmill were studied. Their work was highly repetitive and they had no control over the pace at which their work was carried out (machine paced). They were compared with a group of group of 10 low stress workers who had more control over their workload. The levels of adrenaline and noradrenaline (stress hormones) in their urine was measured both at work and in their free time, and their number of illnesses and absences from work were recorded.

Results: The people in the high stress group had higher levels of stress hormones whilst at work than those in the low stress group and their levels of illness and absenteeism were also higher.

Conclusions: Repetitiveness, high demand/workload and lack of control were linked to higher levels of stress, which increased illness.

Evaluation

• Measure of stress hormones in the urine is an objective measure of stress levels - reduces the chance of investigator effects and has higher validity than self report measures of stress levels.
• The results of the study were useful to real life - the researchers made practical suggestions to lower absenteeism and reduce workload - they suggested job rotation and allowing workers a higher level of control.
• The sample was culturally biased / ethnocentric as the study only used Swedish people who might find machine based work more stressful than other cultures.

Friedman and Rosenman identified what they called a Type A personality - this refers to a behavioural style which is characterised by high levels of competitiveness, time urgency and anger or hostility. People with Type A personalities are often high-achieving workaholics who multi-task, push themselves to meet deadlines, and hate delays. People with type A personality are more likely to have higher levels of adrenaline and their body could go into fight or flight.

In contrast, Type B personality types are generally patient, relaxed, easy-going, and at times lacking an overriding sense of urgency.

Key Study - Friedman and Rosenman (1974)

Aim: To investigate whether there was a link between Type A personality and the development of heart disease.

Procedure: Over 3000 American men between 39 and 59 were interviewed to identify whether they were Type A personality or Type B. They were monitored for eight and a half years and their lifestyle and levels of health were assessed.

Results: After 8 and a half years, 257 men (from the original 3000+) had developed heart disease. 70% of these were from the Type A group.

Evaluation

• It was a longitudinal study which does give us a good idea of the long term effect of personality factors on stress related illness.
• Friedman & Rosenman did not specify what aspect of type A behaviour might be responsible for heart disease. Later researchers reviewed the original data and found that it was ‘the negative behaviours’ such as hostility that seemed to be responsible.
• Once again this is a natural experiment which uses correlational detail so cause and effect cannot be established.

Hardiness

Whereas people with Type A personality are likely to suffer more from stress relating illness, hardiness is thought to be a 'protective' factor - meaning that those with hardy personalities may be less likely to suffer from stress related conditions.

Hardiness was proposed by Kobasa and Maddi (1977) and is made up of 3 characteristics:

• Control: Those with hardy personalities feel that they are in control of stressful situations - this is very similar to having an external locus of control - they do not feel that their level of stress is controlled by external factors.
• Challenge: They see potentially stressful situations as opportunities for personal growth and development, rather than threats or stressors.
• Commitment: They put 100% into whatever they do and do not give up easily. The feel a strong sense of involvement in the world.

Evaluation

• Kobasa did not state whether all three factors (control, challenge, commitment) were equally important, and further research has concluded that control is probably the most important factor.
• Much of Kobasa's research into the link between hardiness and stress related illness used a white male middle class sample, so it is difficult to say whether her results are generalisable to other populations.
• Research has only shown a correlation between hardiness and stress related illness, so we cannot establish a cause and effect relationship.

Biological Therapy - Drugs

Drugs can be used to combat stress by reducing or eliminating the symptoms of the stress such as fast heart rate. Today there are two main categories:

• Benzodiazepines (Lithium and Valium): These drugs slow the activity of central nervous system (e.g. brain and spinal cord) and enhance activity of GABA causing relaxation.
• Beta blockers: These slow down activity in the sympathetic branch of the ANS by reducing levels of adrenaline and noradrenaline. This reduces blood pressure, heart rate etc. and produces a feeling of calm.

Evaluation

• Quick acting in comparison to some other treatments (e.g. cognitive behaviour therapy).
• Drug therapies treat the symptoms and not the problem itself. Therefore, symptoms may reappear when treatment is stopped.
• Some drugs may have side effects, for example the serotonin reducing effect of BZ's can cause depression. Aggression, short term memory loss and mental confusion are also possible.
• Long-term use can result in tolerance (higher doses are eventually needed to produce the same effect) and dependence.

Psychological Therapy - Stress Inoculation Therapy

Stress Inoculation Therapy (SIT) is a form of cognitive behavioural therapy. The aim is to replace irrational and negative thoughts with more positive ways of thinking about a problem. There are three stages to the therapy:

1. Conceptualisation - The therapist helps the individual to identify their stressors and how they respond to these and how successful these responses have been. Patterns of self-defeating internal dialogue (i.e. negative thoughts) are identified.
2. Skill acquisition and rehearsal - The therapist teaches the client coping skills that may be general or event focused. For example replace negative thoughts with positive ones.
3. Application and follow through - The client applies what they have learned to real life situations.

Evaluation

• SIT does not have any undesirable side effects that might be encountered with drug treatments. Unlike drugs there is also no problems with risk of addiction or withdrawal symptoms.
• SIT addresses the root cause of the problem - why the client is stressed – rather than just removing the symptoms of stress. This means it should have a longer lasting effect than other therapies which just deal with the physical effects of stress (e.g. drug therapy).
• Compared to using drugs it is expensive and time consuming. While drugs work immediately SIT could take weeks and months to follow the three stages and change a client’s behaviour.
• SIT requires clients to be motivated and driven. They have to be prepared to practice new skills and apply them in the real world.