Stress

Stress

1. What is stress?

   • A lack of fit between the perceived demands of the environment and the perceived ability to cope with those demands

2. The Body's Response to Stress

   • The stress response is activated by the brain through various glands, hormones and nerve pathways
   • There are two pathways:
     • The Pituitary-Adrenal Cortex Pathway
       • (Previously known as the HPA)
       • Long-Term Stress
       • The hypothalamus controls the pituitary gland which in turns controls the adrenal cortex. The pituitary gland releases adrenocorticotrophic hormone (ACTH) into the bloodstream. This travels to the adrenal cortex and stimulates the release of corticosteroids which help redirect energy to the muscles
       • Hypothalamus
         • Pituitary Gland
           • Releases ACTH
             • ACTH travels to the Adrenal Cortex
               • Adrenal Cortex releases corticosteriods
                 • Fight or flight response
     • The Sympatho-Medulla Pathway
       • (Known as the SAM pathway)
       • The ANS controls the adrenal medulla (centre of gland in the kidneys)
       • The sympathetic branch of the ANS stimulates the adrenal medulla to release adrenaline and noradrenaline into the bloodstream
         • These stimulate heart rate and blood pressure and mobilise energy resources
           • As a result, oxygen is mobilised to the muscles, as part of the 'fight or flight' response to stress
       • Short-Term Stress
       • Hypothalamus
         • Sympathetic Nervous System
           • Adrenal Medulla
             • Adrenaline or Noradrenaline are released
               • Fight or flight response
   • The Immune System
     • Protects the body from infections by harmful viruses and bacteria. Stress suppresses the immune system. Corticosteriods stop the production of lymphocytes
     • Lymphocytes (White Blood Cells)
       • Lymphocytes destroy infectious agents. After short term stressors immune system is able to regain normal function. This is much more difficult if the stressor is long term
     • The Effects of Stress on the Immune System
       • Kiecolt-Glaser et al (1984)
       • Aim
         • To investigate whether the stress of important examinations had an effect on the functioning of the immune system
       • Procedures
         • This was a natural experiment
         • Blood samples were taken: a) one month before their final examinations (relatively low stress) and b) during the examinations (high stress)
         • Immune function was assessed by measuring T cell lymphocyte activity in the blood samples
         • The students were also given questionnaires to assess psychological variables such as life events and loneliness
       • Findings
         • T cell activity was significantly reduced in the second blood sample, taken during their final examinations, compared with the first sample
         • T cell activity was most reduced in participants who also reported high levels of life events and loneliness
       • Conclusions
         • Examination stress reduces immune function, potentially leaving the individual vulnerable to illness and infections
         • Immune function is also affected by psychological variables such as stress of life events and feelings of loneliness. These long-term stressors may make individuals more vulnerable to the added effect of short-term stressors such as examinations
       • Evaluation
         • This study used medical students, who might be considered a non-representative group. This limits the extent to which these results can be generalised to other groups in society
         • This used a volunteer sample, which means that the participants would have been more confident, therefore making results less representative
         • High reliability
           • The results are in line with studies of other groups, e.g. women going through divorce and carers of Alzheimer's disease patients

3. The Autonomic Nervous System (ANS)

   • Located in the peripheral nervous system
   • Controls functions like heart rate, blood pressure and homeostasis (regulation of hormones)
   • Made up of two branches:
     • The Sympathetic Branch
       • Stimulates bodily functions (e.g. speed up heart rate)
       • Examples of functions
         • Increases heart rate
         • Releases glucose into blood
         • Increases blood pressure
         • Widens the bronchi in the lungs
         • Slows digestion
         • Dilates pupils
     • The Parasympathetic Branch
       • Returns bodily functions to normal (e.g. reducing heart rate)
       • Examples of functions
         • Returns digestion to normal
         • Decreases heart rate
         • Decreases blood pressure
         • Narrows bronchi
         • Contracts pupils
         • Stores glucose in the liver as glycogen

4. Life Events

   • In 1967, Holmes and Rahe came up with the idea of a 'social readjustment rating scale' (SRRS)
   • This was an attempt to quantify life changes - any change in your life that might cause stress or readjustment
   • Scores are calculated for a person's experiences over the past year. High life change scores (300+) are related to relatively high frequency of illness, accidents and athletic injuries
   • Rahe conducted a study on 2700 US Navy personnel and found that stress correlated with illness (positive correlation)
     • Criticisms
       • Individual Differences
         • People will find the same events different stress levels
       • Positive / Negative Events
         • Have the same score; e.g. change in financial status
       • Significant Life Events
         • People who do not score high can still be stressed
       • Culture Specific
         • This study was conducted in the US, therefore events are culture specific
       • Retrospective Self Report
         • Results relied on participants opinion which might not be remembered/presented accurately

5. Stress & Personality

   • In the 1970s, Friedman and Rosenman carried out a nine year study of 1000 people to try and find out if personality type affected stress levels.
   • They came up with the idea of the 'Type A' personality
   • Type A Personality
     • Competitive
     • Time-conscious
     • Easily frustrated with others
     • Researchers have suggested that this sort of person would be more likely to show more risky behaviour such as smoking, poor diets and so on
   • Friedman and Rosenman's Study (1974)
     • Aim
       • To investigate links between the Type A behaviour pattern and heart disease
     • Procedure
       • Using structured interviews, 3200 Californian men, aged 39 and 59, were categorised as either Type A, Type X (a balance between Type A and B) or Type B (the opposite of Type A; i.e. more relaxed)
         • This large sample was followed up for eight and a half years to assess their lifestyle and health outcomes
     • Findings
       • By the end of the study, 257 men in the sample had developed CHD, of which 70% were from the Type A group - twice the rate of heart disease found in the Type B group
         • This difference in the incidence of CHD between the two groups was independent of lifestyle factors known to increase changes of CHD
     • Conclusion
       • The Type A behaviour pattern increases vulnerability to heart disease. Behaviour modification programmes to reduce Type A behaviour should result in a reduced risk of heart disease

6. Sources of Stress

   • Life Events (see yellow)
   • Environment
     • Predictability and control
   • Work
     • Role conflict
     • Shift work
     • Interpersonal relationships
     • Environment
       • Heating, lighting, personal space, intense noise
     • Work-Home Balance
       • Demands of the home life can often conflict with demands at work
     • Workload
       • Having a either too much or too little to do
     • Research
       • Marmot (1977)
         • Looking at job strain. Studied civil servants and CHD. Linked stress to having low levels of control
       • Johansson (1978)
         • Looked at Swedish Sawmill workers. Illness rates were higher for the repetitive and highly stressed jobs
       • Methodology and Ethics
         • Self Report Questionnaires
           • Behaviours such as smoking are risk factors. These could have been underestimated
         • Biased Sample
           • Sample was of civil servants, and therefore is not a representative of the whole population
       • Evaluation
         • Kivimaki et al
           • Found support for Marmot when he did a meta-analysis study across Europe, the US and Japan. High stress jobs = CHD
         • Keenan & Newton
           • Found that interviews were more relevant that questionnaires, when assessing stress
         • Individual Differences
           • Lazarus' Transactional model argues that it is a person's perceived ability to cope, rather than the actual stress of the job
   • Type A Personality (see turquoise)
   • Hassles and Uplifts Scale
     • Lazarus
     • Rather than major life changes, it is day-to-day hassles or small uplifts that determine our overall levels of stress
     • It has been found that high scores on 'hassles' (e.g. stuck in traffic or minor arguments) correlated with symptoms of anxiety disorders and depression
     • Bouteyre et al (2007)
       • Investigated the relationship between hassles and mental health
       • Found that 41% of French students in the study suffered from depression and that this correlated with lots of daily hassles
     • Gervais (2005)
       • Asked nurses about the hassles of their work and found that negative feelings (e.g. cancelling treatment due to unavailable beds) increased job strain and performance
       • However, these were counteracted by uplifts (e.g. compliments from patients)
     • Evaluation
       • The Accumulation Effect
         • Hassles make us stressed more than major life events, small things can accumulate until they cause a major stress reaction
       • The Amplification Effect
         • Major life changes may make us more vulnerable to making silly errors and we create our own hassles

7. Stress Management

   • Coping with Stress
     • Emotion Focused & Problem Focused Approaches
       • Roth & Cohen
         • Approach (long-term) and avoidant coping (short-term)
       • Problem focused
         • Addressing the practical side of a situation
       • Emotion focused
         • Targets the emotional side
       • NB: These are not opposites and some people use both. Evaluation: A flexible and practical approach
   • Biological Approach
     • Physiological therapies are used with many psychological disorders, e.g. stress or depression. Most physiological therapies rely on drugs
     • Drugs are especially designed to act on the bodily responses - or symptoms of stress
     • Two types of drugs are used to treat the symptoms of stress
       • Benzodiazepines (BZs)
         • They are the most prescribed drugs used to treat stress and anxiety disorders. Examples include Librium, Valium and Mogadon
         • They increase the action of the neurotransmitter GABA (a chemical which reduces activity in the brain)
         • As a result, the brain's output of excitatory neurotransmitters (chemicals) is reduced, and the person feels calmer
         • Serotonin is a neurotransmitter than has an arousing affect in the brain. BZs reduce serotonin activity, which then reduces anxiety
       • Beta-Blockers
         • These reduce the activity of adrenaline and noradrenaline, which are part of the SAM response to stress
         • Beta-Blockers bind to the receptors on the cells of the heart and other parts of the body that are usually stimulated during arousal
         • Therefore, the heart will beat slower, with less force, resulting in a fall in blood pressure, and therefore less stressed. The person feels calmer and less anxious
     • Advantages & Disadvantages
       • Advantages
         • Speed and effectiveness
           • Drugs can work quickly, rapidly reducing dangerous symptoms, such as raised blood pressure, or reducing disabling levels of stress-related anxiety
         • Availability
           • Drugs can be prescribed immediately. In addition, the range of treatments available is increasing rapidly, with newer agents such as angiotensin-converting enzyme inhibitors (e.g. captopril) providing a variety of ways of tackling the symptoms of stress
       • Disadvantages
         • Dependency
           • Long-term use can lead to psychological and physical dependency. A proportion of people trying to come off BZs will experience a physical withdrawal syndrome, with symptoms such as increased anxiety, tremors and headaches. BZs should only be prescribed for short periods of a week or so, to help cope with short-term stress. Dependency is far less of a problem with beta-blockers, as they do not have a significant effect on central brain mechanisms
         • Tolerance
           • Tolerance to the effect of BZs develops with regular use, i.e. the original dose of the drug has progressively less effect and so a higher dose is required to obtain the original effect
         • Side Effects
           • All drugs have side effects. BZs can cause drowsiness and affect memory. BZs cause a specific deficit in episodic memory (memory for recent events), rather than other aspects of memory such as ability to remember a phone number in short-term memory or recall of long-term memories. Most people who take beta-blockers experience no side effects, or only minor ones such as fatigue or cold extremities (e.g. hands and feet). With people suffering from asthma or other breathing difficulties, however, because beta-blockers can narrow the airways, this can make breathing symptoms worse
         • Only Target Symptoms
           • Drugs treat symptoms, not causes. Many stressors are essentially psychological, so drugs, while helping in the short term, may prevent the real cause of stress being addressed. They are best used to manage acute (short-lived) stressors, such as the initial shock of a bereavement, or examinations. They are most effective when psychological coping techniques are employed at the same time
   • Psychological Approach