Explain the reaction of the body to stress according to General Adaptation syndrome.

Reaction of body to stress according to GAS given by Selye:-

Sely observed patients with various injuries and illnesses in hospitals. He noticed a similar pattern of bodily response in all of them. He called this pattern the General Adaptation Syndrome.

Three stages of GAS model to study the effect of variety of stressors on body

1. Alarm reaction
2. Resistance
3. Exhaustion

Alarm reaction stage : The presence of a noxious stimulus or stressor leads to activation of the adrenal- pituitary-cortex system. This triggers the release of hormones producing the stress response. Now the individual is ready for fight or flight.

Resistance stage: If stress is prolonged,the resistance stage begins. The parasympathetic nervous system calls for more cautious use of the body’s resources. The organism makes efforts to cope with the threat, as through confrontation.

Exhaustion stage: Continued exposure to the same stressor or additional stressors drains the body of its resources and leads to the third stage of exhaustion. The physiological systems involved in alarm reaction and resistance become ineffective and susceptibility to stress-related diseases such as high blood pressure becomes more likely.