2. STRESS  Stress: Response of the body to any demand of it, usually a perceived emergency  Fight or Flight used to be fine, but it no longer effectively explains stress! 1.Modern danger is not often physical, but our body automatically produces physical energy. So we have  physical energy, but no outlet! 2.Stress often extends beyond a ‘moment’ of crisis Chronic stress  heart disease, infection, memory problems, depression Genetic Predisposition + Environmental Triggers =  Chance of Depression (Diathesis Stress Model – Moffitt, 2003)

3. General Adaptation Syndrome (GAS) Selye (1978)  Hypothalamus IMMEDIATELY signals the adrenal glands to release adrenaline and noradrenaline via the central nervous system.  Adrenaline & Noradrenaline o  Heart Rate,  Blood Pressure, surge of energy o  Growth,  Digestion HPA Axis  Hypothalamus SIMULTANEOUSLY signals the Pituitary Gland.  Pituitary gland releases the hormone ACTH ACTH activates the Adrenal Glands  cortisol & glucocortisoids Chronic elevated levels = suppression of immune system, increased blood pressure, etc. 1.ALARM- preparing for fight or flight. Body reacts in two ways…

4. A “negative feedback loop” system keeps stress hormone levels balanced. High levels of cortisol trigger the hypothalamus to reduce production of CRH (the chemical that activates the pituitary gland).

5. General Adaptation Syndrome (GAS) Selye (1978) 2.RESISTANCE- “Coping”  Outward signs of arousal disappear  Internally, stress hormone production continues.  Cortisol & glucocortisoids levels remain high.  Chronic elevated levels = suppression of immune system, increased blood pressure, fatigue and depression.

6. General Adaptation Syndrome (GAS) Selye (1978) 3.EXHAUSTION  Body’s resources are depleted = immune system crashes People and Animals get sick and susceptible to disease.

7. A Barometer of Stress  Holmes examined case histories of 5,000+ patients to develop a ‘stress barometer’ of life changes. Each stressful event adds to your score. More stressful events are ‘worth’ more ‘points.’  Rahe (1972) Used the stress scale as a predictor of illness over 12 months Those who underwent the most life changes (score of 150+) had 2x the illnesses of the lowest category Stress linked to worse health! Research is CORRELATIONAL! o Are positive changes as damaging as negative changes? o Is one major change as damaging as many minor changes?