Physiological Stress Responses Short term stress response n

Physiological Stress Responses Short term stress response n n The HPAA The fight/flight response n The general adaptation syndrome www. psychlotron. org. uk Long term stress response

General Adaptation n Rats exposed to a variety of severe but nonlethal stressors Exercise, injury, mutilation, poisoning A long-term response to stress was observed that was independent of stressor type www. psychlotron. org. uk Selye (1936)

General Adaptation Alarm n n Immediate response to stressor Fight or flight n n n Body tries to adapt to stressor Hormonal changes to cope with stress Conservation of resources Effects on activity level, feeding etc. Not necessarily harmful www. psychlotron. org. uk Resistance

General Adaptation n n Total depletion of coping resources Metabolic changes Decline in immune functioning Increased susceptibility to infection www. psychlotron. org. uk Exhaustion

General Adaptation Adrenal Glands become enlarged Stomach develops ulcers www. psychlotron. org. uk Thymus shrinks

General Adaptation Ethical objections to use of animals n n Deliberate infliction of pain & stress Could alternative methods have been used? n n Rat and human physiology have similarities and differences Human stress is mediated by psychological factors www. psychlotron. org. uk Problems generalising