Transcript Document
Stress and Illness – Key point If you repeatedly turn on the stress-response, or if you cannot appropriately turn off the stressresponse at the end of a stressful event, the stressresponse can eventually become as damaging as some stressors themselves. A large percentage of stress-related diseases are disorders of excessive stress-response. Robert Sapolsky– (show clips from Stress – Portrait of a Killer) Stress and Illness – • What is the relationship between stress and illness? – Stress – Stress changes in physiology changes in behaviour • Moderating factors: Coping, social support, personality, and control Health Consequences of Negative Emotions Coronary Heart Disease and Stress • Rates of CHD is higher in those with high stress jobs. Why? – BP chronically elevated (wear and tear!) – Epi circulating platelets clump together – Atherosclerosis (plaques) • Kaplan’s research with monkeys (re: social stress & unstable hierarchy) Immunity and Stress T cell Immune System Overview Psychoneuroimmunology (PNI) • Subfield of health psychology that emphasizes the interaction of psychological, neuroendocrine, and immunological processes in stress and illness • An individual’s psychological state influences the immune system via the nervous system PNI: From stressor to illness • The magnitude and frequency of the stress response regulate immune competence (e.g., via glucocorticoids) • Level of immune competence determines susceptibility to disease PNI Studies • Immunosuppression has been linked to divorce, bereavement, unemployment, exam periods, occupational stress, and stressful bouts of exercise – e.g., Life stress and exposure to cold viruses • Wound studies (Kiecolt-Glaser) • Animal studies show that tumor cells grow more rapidly in animals exposed to electric shock, loud noise, or other stressors Sapolsky’s baboons • Primate Research Findings: • High and Low Social Status – High cortisol is associated with low social status (instability and less controllability) – Low status – Fewer lymphocytes and weak immune system Sapolsky’s baboons Studies with dominant male baboons suggest that attitude (“personality”) and “culture” are also important (i.e., just being alpha male isn’t necessarily good, if one is highstrung about it…) Forest-troop (killed by dump TB) In humans…