Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Intro, hpa and sam


Published on

  • Be the first to comment

Intro, hpa and sam

  1. 1. Stress!
  2. 2. Discussion1. Describe an occasion when you‟ve felt under stress2. What type of emotions do we feel when we‟re stressed?3. What physiological changes are you aware of when you‟re stressed?4. Define stress
  3. 3. What is stress? “When an imbalance or discrepancy exists between perceived demands and perceived coping resources, then a state of stress exists” Cox & Mackay (1978)Individual Differences?Do we all get stressed from the same things?Why are there individual differences in stress?
  4. 4. Body responseHow does your body respond when you‟re stressed?What changes are you aware of? Increased Increased Increase in HR? BR? energy?Why do you think these changes occur?
  5. 5. Fight or Flight• The stress response is „adaptive‟ (important for survival) because the physiological changes are perfect for fight or flight• Basically, your physiology alters so you can either fight the stressor or run from it!
  6. 6. Fight or Flight StressorAny event that causes a stressreaction in the body. Stressors include environmental stressors (workplace/college) and life events (divorce, illness)
  7. 7. Nervous System Central NS Peripheral NSBrain Spinal Cord Somatic Autonomic Sympathetic Parasympathetic Conserve Use Energy Energy
  8. 8. Autonomic Nervous System Sympathetic Parasympathetic• When we’re stressed • When we’re relaxed• Increase heart rate • Decrease heart rate• Decrease stomach • Increase stomach activity activity• Pupils dilate • Pupils contract• Glucose is released • Glucose is stored Only one part of the ANS can be activated at any one time – they work antagonistically
  9. 9. Stress response systems...The hypothalamus is alerted whenever a stressful situation is identifiedThere are 2 systems designed to help us cope with stress:1. Sympathetic-Adrenal-Medullary Pathway (SAM) for acute stress2. Hypothalamic-Pituitary-Adrenal System (HPA) for chronic stress
  10. 10. Acute stress - SAMAcute Stressor (e.g. Slipping on ice)Hypothalamus activates the...SNS which activates the...Adrenal Medulla which releases...Adrenaline and Noradrenaline which equips for...Fight or Flight by causingPhysiological reactions such as increased BP, HR, dilated pupils
  11. 11. Chronic Stress - HPAChronic Stressor (e.g. Exam worry/anxiety)Hypothalamus releases...CRF which stimulates thePituitary Gland which releasesACTH stimulating the...Adrenal Cortex which produces...Corticosteroids which stimulates the...Liver to release energy(Immune system is suppressed) This usually takes 20 minutes to take effect
  12. 12. Hypothalamus Pituitary Gland Adrenal Medulla HPA SAM (Chronic) (Acute) Adrenal Cortex AdrenalineCorticosteroids Fight or Flight Liver releases Physiological energy Reactions
  13. 13. Poster activity – 20 minutes• In pairs you are to draw an outline of a person• In one colour you are to map out the physiological response to an acute stressor (you will have 10 minutes for this)• In another colour you are to map out the physiological response to a chronic stressor (you will have 10 minutes for this)
  14. 14. Mnemonics!SAM - Acute HPAA - ChronicA Always C ChildrenH Have H Have C CrazyS Some P PartiesA Anaesthetic A AlwaysA Aside A AddingN For C ClownsP Pupils L Lots I Italian S Stallions
  15. 15. Evidence to support the role of the adrenal glands in the stress responseFor example, Tyrell & Baxter (1981) found that thosewho cannot produce stress hormones have to besupplemented to survive This is positive because it shows that the release of stress hormones is vital in the stress response,supporting the biological evidence presented by SAM and the HPA
  16. 16. The physiological account of stress can be criticised for ignoring individual differencesFor example, Mason (1975) compared reactions of stressors andfound that adrenaline and noradrenaline patterns varied betweenparticipantsThis is a weakness because it means that the physiologicalexplanations of stress is inadequate because not everyonewill respond to the same stress in the same way - what one person finds extremely stressful another might find enjoyable (e.g. Exams)
  17. 17. The physiological approach suggests that people are passive in their stress response – ignoring psychological factors For example, Mason (1975) suggests that there is an active process of psychological appraisal when people are confronted with a stressorThis is a weakness because it indicates that how an individual views the stressor will affect their bodily response – and this is ignored by the physiological explanations of stress
  18. 18. TASK!• You will be split into 2 groups, each group will be give one response to stress (SAM or HPA)• In your groups you are to organise yourselves and „act out‟ the response to stress• You have 15/20 minutes in which to do this• This will all be filmed – make it a good‟un!