Stress as a bodily function.

Stress is a type of alarm reaction, it is both a psychological and a physiological response to the environment.Your brain produces a stress reaction when you are in a situation that is physically or mentally demanding.

When psychologists talk about 'stress' they may refer to the

causes of stress reactions, which are called Stressors, or to the effects of stress reactions on our physical and mental functioning.

Your is the threatens to (state

of balance) - if there are around, it s off an . The your

- sometimes known simply as the Stress

the the your

as shown on the left.

What if you are not in a situation in which it's OK to suddenly get up and run a four-minute mile round the block?

Well, that's when various unpleasant effects may set in, such as throbbing headaches, irritability, tense neck and shoulders, dried up mouth and butterflies in the stomach. Most people experience this sort of stress sometimes.

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Stress as a bodily function.

NERVOUS SYSTEM

Processes, interprets and stored information; issues orders to muscles, glands and organs.

CENTRAL NERVOUS SYSTEM

(CNS)

SPINAL CORDBridge between brain and peripheral nerves

BRAIN

PERIPHERAL NERVOUS

SYSTEM (PNS)Transmits info. To and from the CNS

SOMATIC NERVOUS

SYSTEM (SNS)Controls skeletal muscles

AUTONOMIC NERVOUS

SYSTEM (ANS)Regulates glands, blood vessels, internal organs etc.

PARASYMPATHETIC

NERVOUS

SYSTEM (PNS2)Conserves energy, maintains quiet state

SYMPATHETIC NERVOUS

SYSTEM (SNS2)Mobilises body for action energy output.

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Stress as a bodily function.

The flow diagram below shows what goes on in the body when the brain detects a potentially harmful 'stressor'

stress hormones circulating in the bloodstream andthe neural effects of the sympathetic nervous system combine to create the 'fight-or-flight' response.

The hypothalamus plays a key role in the control of the endocrine system. There is a complex feedback system between the hypothalamus, sympathetic nervous system, the pituitary gland and the secretions of the adrenal glands.The adrenal glands are found on top of your kidneys - they secrete epinephrine(otherwise known as adrenaline) and other 'stress hormones'. The activity of your adrenal glands is crucial to your mood, energy levels and ability to cope with stress.

Adrenaline 3

•This maintains a steady supply of energy, butalso suppresses the immune system.

•These cause bodily changes that prepare the body for fight or flight. E.g. increased heart rate. Non-essential processes (like digestion) are inhibited

•The hypothalamus (area of the brain that responds to stress) releases noradrenaline (a chemical messenger)in response to a stressor.

•This stimulates the Adrenal Medulla to release adrenaline ( a chemical messenger)

•The hypothalamus registers the presence of a continuing stressor and stimulates the pituitary gland to release adrenocotrophic releasing factor (ACTH)

•Which releases Corticosteroids such as Cortisol

THE SYMPATHOMEDULLARY SYSTEMBODY’S RESPONSE TO ACUTE STRESS

HYPOTHALAMIC PITUITARY ADRENAL (HPA) SYSTEMBODY’S RESPONSE TO CHRONIC STRESS

Stress as a bodily function.

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Stress as a bodily function.

•Increased activity of the sympathetic medullary pathway and the pituitary adrenal system.•Occurs 6-48 hrs after stress•Includes a loss of muscle tone and a drop in body temperature.

• Stage of adaptation and also involves the activity of the pituitary- adrenal system.•There is an increase in the size of the adrenal gland and a reduction in some pituitary functions. E.g. Reduced production of growth hormone.•More careful use of body’s resources.•If the stress is not too great the body will return to a near-normal state.

•When the stress is very prolonged, the physiological systems involved in the alarm reaction and resistance stage become ineffective•The damaged adrenal cortex can lead to failure of the body’s parasympathetic system and the collapse of the body's immune system.•Stress related disease become more likely, Selye called these: Diseases of adaptation

He studied humans and animals and found that we respond to stressors through a three-staged physiological response called; General adaptation Syndrome (GAS)

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Stress as a bodily function.

Helps us understand the link between stress and illness, particularly in terms of biological methods in reducing stress.

It ignore the idea that the stress response varies depending on the stressor and the individual

It assumes people are passive in their response to stress, even though there is evidence that people actively appraise the situation (Mason 1975)

[And the bodily response research in general]

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Research has shown strong links between prolonged stress and many disorders, mentally and physically. The immune system is easily affected by stress.

Stress as a bodily function.

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.

Direct biological effects e.gPhysical strain, hormone changes

Maladaptive coping behaviour e.g. smoking, drinking alcohol

Emotionally mediated effects on diet and activity level

Stress can also affect the immune system by raising blood pressure. Hypertension (consistently raised blood pressure over several weeks) is a major risk factor in coronary heart disease (CHD). However, CHD can also be caused by many other factors.

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Stress as a bodily function.

Kiecolt-Glaser et al. (1984)•Investigated whether stress of important examinations has an effect on the functioning of the immune system•This was a natural experiment. The researchers took blood samples from 75 first year medical students (49 males and 26 females), all of whom 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. 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 (A02)•This was a natural experiment which also used a real life stressful situation, so ecological validity is high.•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. It is very unlikely to gain complete control over these extraneous variables.•Measuring T cell activity is an objective way of measuring immune system functioning so demand characteristics should not be a problem.•Sampling bias: Participants were all students so results may not be generalisable to the general population.

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Stress as a bodily function.

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 - A02• 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.

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.

Friedman and Rosenhan (1974)

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Stress as a bodily function.

You should be aware that stress might lead to behaviour, such as smoking or overeating, which increases the risk of serious illness - so the link with the original source of stress is indirect.

The incidence of cancer has been correlated with high stress levels.

Jacobs and Charles (1980) found that cancer patients - for example, child cancer patients, often suffered high levels of stress before the diagnosis of their illness.

Tache et al (1979) found the incidence of cancer to be higher in those with a poor 'social support network' such as the widowed, divorced or separated.

Here's how stress might lead to heart disease: Stress-related behaviour such as smoking or eating lots of fatty foods will speed up the hardening of the blood vessels stage…

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Life Changes

Stress as a bodily function.

Holmes and Rahe 1970 – Investigated whether scores on the

Holmes and Rahe Social Readjustment Rating Scale (SRRS) were correlated withthe 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, 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). 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.

•The SRRS does not take individual difference into consideration. 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.•Correlation does not equal causality•The sample has a gender bias as it is based on males, meaning we cannot generalise 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”, e.g. such as losing your keys.•The study may lack validity due to social desirability. A with moist questionnaire studies, people may li 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.

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Daily Hassles

Stress as a bodily function.

Kanner et al (1981)•Interested in 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.•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 correlation does not equal causality•The sample is culturally bias / ethnocentric as it is based on 100 Americans who may 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. As 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.

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Stress as a bodily function.

Marmot et al (1997)7000 Civil servants were surveyed about their grade of employment, the level of support and how much control they felt they had.ResultsThe medical histories were followed up 5 years later, those who were in lower grade jobs with less support and control had higher levels of CHD. Participants on the lowest grade were 4 times more likely to have a heart attack than those on the highest grade.ConclusionBelieving you have little control increases workplace stress and the development of illness.Evaluation

The study only included ‘white collar’ workersSmoking was common in those who developed illness –Smoking is a factor of CHD- .Other factors such as Diet and exercise were not taken into considerationThe research is correlationalQuestionnaires- not everyone may have been truthful

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Stress as a bodily function.

Kobasa and Maddi (1977)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 - A02• 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.

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Stress as a bodily function.

Skinner (2003)

1.Problem solving2.Support seeking3.Escape4.Distraction5.Positive cognitive restructuring

6.Rumination – Refocusing on the causes of something-

7.Helplessness8.Social withdrawl9.Emotional regulation

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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 - A02• 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.

Stress as a bodily function.

Biological Therapy - Drugs

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Stress as a bodily function.

Psychological Therapy - Stress Inoculation Therapy (S.I.T)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:

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. 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. Application and follow through - The client applies what they have learned to real life situations.

Evaluation - A02• SIT does not have any undesirable side effects that might be

encountered with drug treatments. 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 .

• Compared to using drugs it is expensive and time consuming. • SIT requires clients to be motivated and driven.• Evidence that it is effective- Fontana found that after 6 sessions of

SIT, Pps had lower heart rates and levels of anxiety• Most of the Pps were white middle class so it is not generalisable.

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