Biological Psychology - Stress Revision of whole topic

Specification Stress as a bodily response The body’s response to stress, including the pituitary- adrenal system and the sympathomedullary pathway in outline Stress-related illness and the immune system Stress in everyday life Life changes and daily hassles as sources of stress Workplace stress including the effects of workload and control Personality factors, including Type A and Type B behaviour, hardiness Psychological and biological methods of stress management, including stress inoculation therapy and drugs

The body’s response to stress The symapthetic-medullary pathway (SMP) and the pituitary-adrenal system (PAS)

The Body’s Response to ACUTE Stress (SMP)

BOOST OF OXYGEN TO BRAIN & MUSCLES SUPPRESSION OF DIGESTION The effects of noradrenaline and adrenaline NoradrenalineAdrenaline Acute Stress SWEAT GLANDS PRODUCE MORE SWEAT BRONCHIAL TUBES IN THE LUNGS DILATE FOR GREATER OXYGEN INTAKE INCREASED PUPIL SIZE ADRENAL MEDULLA RELEASES ADRENALINE GLYCOGEN IN THE LIVER IS CONVERTED TO GLUCOSE HEART RATE INCREASES

The Body’s Response to CHRONIC Stress (PAS)

What happens when the stressor is removed? When a short term stressor is removed, the parasympathetic branch of the autonomic nervous system (ANS) quickly kicks into action to restore the body to homeostasis (a sense of physical balance). This means that systems that were aroused are now lowered to normal levels. For example: Heart rate is lowered Blood pressure is lowered The digestive process returns to normal The sympathetic branch of the ANS is often the ANS is often called the ‘rest and digest’ system called the ‘rest and digest’ system

Stress and the immune system Kiecolt-Glaser and Cohen

How stress affects the immune system The immune system is a complex collection of biological structures and processes which protect the body from disease by identifying and destroying viruses, bacteria and cancer cells (collectively known as antigens). When we are chronically stressed, cortisol is released as a part of the pituitary adrenal system. One of the effects 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.

Short term stress: Kiecolt-Glaser et al. (1984) Aim: To investigate the effect of exam stress on the immune system Procedure: Blood samples were taken from 75 first year medical students a month before their exams and again on the day of their first exam. The level of killer T cells (a type of white blood cell) in the blood was measured. The students also filled in questionnaires to measure psychological factors such as social support and life events. Results: There were significantly fewer killer T cells in the second sample compared to the first. This was especially true for students who reported loneliness and a high number of recent life events. Conclusions: Even the relatively short term stress of exams can be damaging to health, especially if experiencing other stressors such as loneliness.

Evaluation of Keicolt-Glaser et al This was a natural experiment (no manipulation of the independent variable) which also used a real life stressful situation, so ecological validity is good. However, we cannot establish cause and effect (between stress and a weakened immune system) using a natural experiment. Measuring T cell activity is an objective way of measuring immune system functioning so investigator effects should not be a problem. Participants were all students so results may not be generalisable to the general population. However, other studies have shown similar effects with other sections of the population.

Long term stress: Cohen et al (1993) Aim: To investigate the role of general life stress on vulnerability to the common cold. Procedure: 394 healthy participants completed questionnaires to assess their perceived levels of current stress and the number of life events experienced in the previous year that they felt had a negative effect. They were then exposed to the common cold virus (via nasal drops). Results: 82% of participants developed the common cold. Those with higher stress scores were most likely to develop a cold. This was true even other possible contributing factors such as the time of year, diet and amount of sleep were taken into account. Conclusions: Life stress increases vulnerability to the common cold.

Evaluation of Cohen et al This was a natural experiment (stress levels were not manipulated) so it is high in ecological validity. However, this means that cause and effect (between stress levels and development of the common cold) cannot be established. Stress levels were measured using a self report method so participants may not have been honest about how stressed they felt (social desirability?) or they may not have remembered all life events in the previous year.

Further research into the effects of stress on the immune system  Kieocolt Glaser et al (2005) studied the effects of interpersonal conflict on wound healing. They found that blister wounds on the arms of married couples healed more slowly when they were in conflict (arguing, disagreeing).  Kiecolt Glaser et al (2000) - yes, her again! - found that long term caregivers had poorer immune system functioning than a matched control group.  The death of a close relative (spouse, child, parent) has also been found to reduce the number of white blood cells available to fight infection.

Stress and cardiovascular disease (briefly) Acute and chronic stress can lead to: High BP CHD Stroke The illnesses above are also linked to other lifestyle factors too, such as smoking, diet etc. Below are reasons why stress has been implicated in the development of these illnesses: Stress activates the SNS leading to an increase in heart rate and BP. An increase in heart rate wears the blood vessels. Stress leads to increased glucose levels which can clump the blood vessels (see image).

Sources of stress Life events and daily hassles

Social Readjustment Rating Scale: Holmes and Rahe (1967)  Developed in 1967 by doctors Holmes and Rahe to investigate whether stressful life experiences had an effect on health.  They compiled a list of stressful events using the medical records of their patients and then asked hundreds of men and women of various ages and backgrounds to rate each event on the amount of readjustment they would require (in other words, how stressful they thought they would be).  Participants judged the death of a spouse as the most stressful event so this was given a Life Change Unit (LCU) score of 100. Other events, such as divorce and moving house, were then assigned an LCU score based on this.  They then carried out a number of studies (e.g. Rahe et al, next card) to test whether life events in the past year correlated with illness. They believed that a score of 300 or more would increase the odds of stress related illness by 50%.

Evaluation of the SRRS The SRRS assumes that all changes are stressful, even if they are positive (e.g. marriage) Some of the items are ambiguous (unclear). E.g. revision of personal habits. Does not consider individual differences in how people perceive events e.g. change of job could be positive or negative. Most of the events on the SRRS are not every day experiences, so a person could have not experienced any of them in the past year but still feel stressed. This has been investigated by later research on daily hassles.

Aim: To investigate whether scores on the SRRS correlate with subsequent illness. Procedure: 2500 male American sailors completed the SRRS to assess how many life events they had experienced in the last 6 months. They then went on a 6 month tour of duty and a record was kept of their health during this time. Instances of illness were correlated with their scores on the SRRS. Results: A positive correlation was found between the score on the SRRS and the number of illnesses during the 6 month period. Conclusions: Experiencing a high number of life events can cause illness. Research into the effect of Life Events on Health - Rahe et al (1970)

Evaluation of Rahe et al This study uses a correlation, which means although we can establish a link between life events and illness we cannot establish a cause and effect relationship. Although the correlation was positive it was very small (0.118). A good size sample was used = good population validity = should be able to generalise findings to target population. But all participants were male American sailors, so the results may not be generalisable to other sections of the population.

Daily Hassles and Uplifts Daily hassles are relatively minor events that happen during the course of a normal day e.g. too many things to do, conerns about weight, etc. Daily uplifts are positive everyday experiences that are thought to counteract the effects of daily hassles e.g. completing a task or talking to friends. DeLongis, Lazarus and Folkman compiled a list of 117 daily hassles and 135 daily uplifts which formed the Hassles and Uplifts Scale. The link between stress and daily hassles and the possible positive effect of daily uplifts have been investigated by a number of studies including DeLongis et al (1982) - next slide.

Daily Hassles

Research into the effect of Daily Hassles and Uplifts on health - DeLongis et al (1998) Aim: To investigate the effect of daily hassle and uplifts on health, and to compare this to the effect of life events. Procedure: 100 American men and women aged were asked to complete four questionnaires once a month over a one year period: Daily hassles scale Daily uplifts scale Life events questionnaire Health questionnaire Results: There was a significant correlation between the number of daily hassles recorded and ill health, but there was no effect from daily uplifts. There was a significant effect from life events, but this was not as strong as daily hassles. Conclusions: Daily hassles are more stressful than life events. This is likely to be because they happen more often and have a cumulative effect. Daily uplifts do not moderate the effect of daily hassles.

Evaluation of DeLongis et al The study used correlational data so cause and effect (between stress and illness) cannot be established because there may be a third variable involved. The sample was made up of mostly well educated, high income, middle aged Americans. This means results may not be generalisable to other countries, age groups, etc. Data was collected using self report methods so participants may have been dishonest or may not have remembered previous life events and health problems = lower internal validity.

Why are daily hassles so stressful? The accumulation effect states that daily hassles are more stressful than (rare) life events as they build up and cause stress reactions. The amplification effect states that major life events make people more vulnerable to daily hassles. E.g. Someone going through a divorce (major life event) will become more stressed by squabbling children (hassles).

Workplace stress Marmot and Johansson

Workplace stress in civil servants – Marmot et al (1977) Aim: To investigate the effects of high workload and low control on stress and illness. In context of sample used (Civil Servants) it was assumed that high grade employees would experience high demand and low grade employees would experience low control. Procedure: Civil service employees in London were invited to take part and 7,372 agreed to take part by filling in a questionnaire (asking about their grade, sense of control, social support, etc) and by having a health check to assess signs of cardiovascular disease. They were reassessed five years later. Results:  1. Higher grade workers developed fewer cardiovascular problems.  2. Lower grade workers expressed a weaker sense of job control and less social support.  3. Workers with cardiovascular disorders were more likely to be low grade workers but they were also more likely to be smokers and be overweight Conclusions: Low control is related to higher stress and greater risk of cardiovascular disease, but high workload is not linked to greater stress and illness.

Evaluation of Marmot et al Sample was biased (only London based civil servants) so may not be generalisable to other cultures/countries or professions. Lower grade workers are also more likely to smoke, live in stressful environments and have poor diets (due to their lower socioeconomic status) and these could have contributed to their higher risk of developing cardiovascular disease, rather than their level of control at work. However, further research (e.g. Johansson et al, 1978) does support lack of control as a risk factor for high stress levels.

Workplace stress in a Swedish sawmill – Johansson et al (1978) Aim: To investigate the effect of repetitiveness, high demand and lack of control on levels of stress at work. 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. They 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 and lack of control were linked to higher levels of stress, which increased illness and absenteeism.

Evaluation of Johansson et al 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. This was a natural experiment so cause and effect cannot be established. Biased sample = low population validity = may not be generalisable to other groups.

Personality factors in the response to stress Type A personality and the Hardy personality

Personality factors and stress – Type A and B behaviour There is some evidence to suggest that some people are more sensitive to the effects of stress than others. 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. In contrast, Type B personality types are generally patient, relaxed, easy-going, and at times lacking an overriding sense of urgency. Friedman and Rosenman believed that Type A personalities were more likely to develop stress related conditions such as heart disease, and carried out further research to test this (next card).

Type A behaviour and heart disease – 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. Conclusions: The characteristics of people with Type A personalities make them more vulnerable to stress related conditions.

Evaluation of Friedman and Rosenman 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. Does not take account of the effect of other personality factors. For example, it is possible to have both a Type A and Hardy personality (next card), and this hardiness may moderate the effects of Type A characteristics. Once again this is a natural experiment, meaning the IV (level of control at work) was not manipulated by the researcher, so cause and effect cannot be established.

The Hardy Personality 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. Kobasa devised questionnaires to assess these characteristics and found that people with high hardiness scores reported fewer instances of stress related illness

Evaluation of The Hardy Personality 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.

Stress management techniques Drug therapy, Deep muscle relaxation and Stress inoculation therapy

Biological methods of stress management – Drug therapy Drugs can be used to combat stress by reducing or eliminating the symptoms of the stress. Anxiolytics (which reduce the symptoms of anxiety) include:  Benzodiazepines (BZ's) - Benzodiazepines (BZs) increase the activity of a neurotransmitter called GABA. GABA prevents other neurotransmitters, such as serotonin and dopamine, from being so effective, thus having a calming effect.  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.

Biological stress management – Drug therapy Most common drug to treat stress and anxiety Slows down the CNS activity GABA is the neurotransmitter responsible for anxiety relief naturally in the body. 40% of neurons in brain respond to GABA BZs enhance GABA BZs also reduce the serotonin activity in the brain as this is the neurotransmitter which causes the arousal; this also reduces anxiety. BZs slow the CNS BZs increase GABA BZs decrease serotonin =LESS STRESS!

Biological stress management – Drug therapy activates SNS Increased heart rate Raised BP Elevated cortisol leads to CHD and lower immune system take a... Beta Blocker (BB) Reduce activity of noradrenaline and adrenaline (acute stress response) BBs... Bind to receptors of heart and other areas of the body which are stimulated by arousal. By blocking these receptors it is harder to stimulate them and so the heart will beat slower, causing less BP and lower heart rate

Evaluation of drug therapy 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 is linked to 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 (where the person can not deal with stressful situations without the aid of medication).

Biological techniques – Progressive muscle relaxation Clients are trained by the therapist to achieve a state of deep relaxation by systematically tensing and releasing muscle groups throughout the body, beginning with the toes and progressing upwards through the body and to the facial muscles. This activates the parasympathetic branch of the autonomic nervous system, which counteracts the stress reaction happening in the sympathetic branch of the ANS and provokes a feeling of relaxation. Eventually the client is able to use this technique independently to help them cope with stressful situations.

Evaluation of Progressive Muscle Relaxation STRENGTHS Research shows that it can be effective if used regularly. Relatively quick and easy in comparison to other treatments. No side effects, unlike drug treatment. Requires commitment from the client to learn the techniques. LIMITATIONS Not suitable for all situations due to time and space constraints (e.g in a car). Only addresses the physical symptoms of stress so does not treat the underlying causes (e.g. stress at work) - therefore may not be an effective long term strategy.

Psychological techniques – Stress Inoculation Therapy The therapist and client establish a relationship. The client is taught about the nature of stress. Conceptualisation Coping skills are taught and practised in the clinic. Skills include relaxation, social skills, attention diversion, time management. Skills acquisition (and rehearsal) Clients apply the skills to different and increasingly stressful situations. Techniques like imagery, modelling and role play used. Client trains others. Application phase Meichenbaum (1985) believed that you cannot control the cause of stress, but you can control the way you think about stressors. SIT is different from other stress management techniques; it works before the stressor is encountered and ‘inoculates’ the individual to cope better in future.

Evaluation of stress inoculation therapy STRENGTHS It is flexible and can be tailored to suit individual needs and different types of stressors. No side effects, unlike drug therapy. Benefits of SIT can be long- term (unlike drugs), and it teaches general coping skills that can be applied to a variety of stressors in the future. It addresses the root cause of the problem - why the client is stressed - so should have a longer lasting effect than other therapies which just deal with the physical effects (e.g. drug therapy). WEAKNESSES SIT requires time, effort and motivation from the patient to learn the techniques and continue to apply them. The skills taught during SIT may be more beneficial than the whole training, e.g. Learning to think more positively. May not work as quickly as drug treatment, but could be combined with drugs for greater effectiveness.