Selye's GAS Model.
GAS: General Adaptation Syndrome:
Selye developed a three stage model of how the body responds to stressors:
Stage 1: Alarm:
the body detects the stressor and the SAM pathway is activated. during this stage, the two hormones; adrenaline and noradrenaline are released, which lead to bodily changes; increased heart rate, muscle tension, perspiration, blood rate and a decrease in digestion.
Stage 2: in this stage, the HPA axis is activated, which releases CRH and ACTH.
Stage 3: the body can no longer cope with the demands of the situation/stressor. high levels of stress hormone and the increase becomes likely.