stress

• general adaption syndrome (GAP)- Selye


  refers to the way in which the body reacts to stress on both a long term and short term basis
• 3 stages of GAS

  • alarm reaction
  • resistance
  • exhaustion
• alarm reaction 


  fight or flight response
• resistance stage 


  bodies short term response to stress

  adrenaline levels drop, cortisol levels in the blood sugar levels rise to provide individuals with energy to resist stress
• exhaustion stage


  if the stressor continues beyond resistance stage, the bodys energy levels will become depleated

  body will be unable to maintain normal functions which will make them more likely to become ill leading to immunosupression
• key study - Selye

  aim

  • look at the short and long term effects of stresss in the context of GAS

  method

  • exposed rats to a variety of stressors

  results

  • rats got sick because of their experiences and had enlarged adrenal cortex and ulcers in the lining of their stomaches

  conclusion

  • supports Selyes prediction that there is an underlying biological underpinning to stress and that GAS is the explanation for the process that the body goes through
• evaluation of GAS 


  evidance that there is an underlying biological response to stress

  research conducted on animals
• Sympathomedullary pathway (SAM)


  refers to the short term stress response

  • fight or flight response
• the SAM pathway

  1. presence of the short-term stressor causes the hypothalamus to activate the sympathetic branch of the ANS
  2. sympathetic branch triggers the activation of the adrenal glands
  3. activation of the adrenal glands causes adrenaline and noradrenaline to be released into the bloodstream to perpare for fight or flight
  4. once the stressor is removed, parasympathetic system returns body back to resting state
• evaluation of SAM 


  research uses findings from animal studies

  • not generalisable to humans
  • older rats had lower levels of adrenaline post stressful situation compared to younder rats

  historically body of stress has been carried out on men

  • represents men well
  • lacks generalisatility for females
  • tend and befriend response
• hypothalamic pituitary-adrenal system (HPA)


  system which activates chronic (long term) stressors
• process of HPA

  1. hypothalamus stimulates the release if the CRH hormone
  2. pituitary gland stimulated by the CRH to release ACTH
  3. ACTH travels in bloodstream and stimulates adrenal gland, which releases stress related hormones- cortisol
• evaluation of HPA 


  research done on the release of cortisol in pregnant women

  • presence of cortisol in the mothers blood stream may have an effect on the unborn foetus

  helps medical professionals to understand the effects of stress on the body over time and how to treat it

  • cortisol can have a damaging effect on the immune system
  • cushings disease
• role of cortisol in the stress response 


  released in during the HPA

  role= to provide blood sugar to supply the body with sufficient energy to deal with chronic stress

  • is good but also problematic
  • indicated that by exhaustion in GAS, supplies will become depleated, and the energy will have to come from somewhere, so other areas have to suffer
• evaluation of the role of cortisol in the stress response

  cortisol has been linked to some negative effects in connection with stress

  • suppression of the immune system
  • large amounts of research into the links between stress and illness

  ethics of animal research
• stress and immunosupression


  immune system acts as the bodies defence systems against illness and disease

  function is to detect foriegn bodies in the organism and destroy them throug invading the pathogens

  • pathogens carry antigens to destroy pathogens

  ordinarily, immune system would function well, but with chronic stress, the release of cortisol has been linked to problems with the immune system

  prolonged exposure to cortisol will cause immunosupression
• Key study


  Kiecoult-Glazer et al
• evaluation of stress and immunosuppression

  application to real life

  • kiecoult-glazer study has clinical implications
  • women who are carers take considerably longer to recover than men

  much of the evidance is correlational in nature

  • difficult to show cause and effect
  • illness cause stress or stress cause illness
• key study of immunosuppression and stress- Kiecoult-Glazer et al 


  AIM

  • investigate the link between high stress and immunosuppression by measuring the natural killer cell activity in fist year medical students approaching their exams
• key study of immunosuppression and stress- Kiecoult-Glazer et al

  METHOD

  • blood samples taken from 75 students a month before their exams and then after their exams had started 
  • Their natural killer cells were measured in both of these samples 
  • PS also completed a questionnaire about on psychosocial topics 
•  key study of stress and immunosuppression

  RESULTS

  • in second sample of blood, natural killer cell activity was reduced and those who scored highly in the questionnaire, had the lowest activity 
• key study of stress and immunosuppression

  CONCLUSIONS

  • findings indicate that stress can lead to immune suppression
  • a persons psychosocial profile can further impact the effectiveness of the immune system 
• cardiovascular system 


  system which is responsable for transporting blood and other nutrients around the body in order to maintain its smooth functioning
• cardiovascular disorders 


  disorders which come as a result of exposing the system to extended periods of stress and can lead to lots of different conditions due to the negative impact of stress and other factors on blood vessels

  • chonory heart disease
  • hyper tension
• relationship between stress and CVDs 


  is indirect or direct

  • stress can lead to these conditions, or individuals with stress may adopt poor lifestyle changes which can havae an effect on their cardiovascular system
• key study on stress and CVDs - Cobb and Rose 


  AIM

  • compare stress and illness rates between airtraffic controllers (high risk group) and second class airmen (low risk) at a US airbase
• key study on stress and CVDs- Cobb and Rose 


  METHOD

  • researchers examined mdeical records of air traffic controllers and the airmen retrospectively
  • both groups were examined by the same group of doctors as it is a requirement in order to renew their aviation licenses
• key study on stress and CVDs- Cobb and Rose

  RESULTS

  • found a higher rate of CVDs in airtraffic controllers, with a 5.6 times higher incidences of new cases of hypertension during a 1 year period
  • and a 4 times higher rate of hypertension in general
  • also found that other stress-related illness were twice as common
• key study on stress and CVDs- Cobb and Rose

  CONCLUSION

  • findings suggest that highly stressful experiences/environments are linked to CVD or certainly increase the risk of them
• evaluation of CVDs 


  -doesnt take into account individual differences

  -research could be seen as deterministic

  -research is correlational, so can therfore not show cause and effect

  • unclear if stress has a direct role in teh cardiovascular conditions or not
  • research shows its more likely to be indirect- difficult to see what part it plays
  • however, would be unethical to do a lab study on if CVDs do cause illness
• sources of stress

  • life changes
  • daily hastles
• life changes 


  meaningful change or transition in a persons life, which requires readjustment as a result to settle into a normal routine again afterwards
• holmes and rahe- life chnages 


  doctors who identified patterns in their behaviours

  • they seemed to be frequently ill after a significant period of change
  • the conclusion they drew if that life change was particularly significant and required a great deal of readjustment then the individual would experience greater stress in the process
  • therefore, leading to ill-health
• results of holmes and rahe

  the more significant the change the higher the life changing units on the holmes and rahe social readjustment rating scale

  • results showed higher correlation between each participants assessment of the life events and readjustments required, suggesting high levels of reliability
  • holmes and rahe argued that individuals who experienced a total of 300+ LCUs in the last 12 months has an 80% chance of suffering from stress
  • those who experience 150 LCUs or below have a 30% change of developing stress
• key study of life changes- Rahe


  AIM

  • to explore the role of life changes in relation to stress and illness
• key study of life changes- Rahe


  METHOD

  • male naval officers took the SRRS in consideration of the previous 6 months before going away on a 6 month tour of duty
  • upon return their medical records were examined in conjunction with their initial SRRS scores
• key study of life changes- Rahe


  RESULTS

  • found a strong correlation between LCUs and incidences of illnesses while they were away
• key study of life changes- Rahe


  CONCLUSIONS

  • given the strong links between stress and the immune system
  • the conculsions draw from these findings is that the life changes will have increased the mans levels of stress and therefore lead to illness
  • suggests that life changes are a potential source of stress
• evaluation of SRRS (Social Readjustment Rating Scale)


  • Requires retrospective data
  • Requires participants to include life events which have happened in the last year
  • Can be a long time to have to remember everything which has happened, therefore prone to inaccuracy
• evaluation of SRRS 


  SRRS lacks temporal validity

  • merage used as their 'main readjustment point', arguing that it would require a large amount of readjustment
  • may have done in the 1960s, but not as much now as the social norms have changed
  • shows how society has changed and therefore attitudes towards what is considered stressfull