Psychology · Ch 3 — Meeting Life Challenges
General Adaptation Syndrome
General Adaptation Syndrome
The Body’s Response to Prolonged Stress
When stress continues for a long time, the body does not just stay in a state of alarm. Hans Selye, a pioneering researcher, wanted to understand what happens to the body under such prolonged stress. He conducted laboratory experiments on animals, exposing them to various stressors like high temperature, X-rays, and insulin injections over extended periods. He also observed patients in hospitals who were suffering from different injuries and illnesses. Across all these cases, Selye noticed a strikingly similar pattern of bodily response. He called this pattern the General Adaptation Syndrome (GAS).
Selye’s model describes three distinct stages through which the body passes when faced with ongoing stress: alarm reaction, resistance, and exhaustion.
The Three Stages of GAS
1. Alarm Reaction Stage
The moment a noxious stimulus or stressor is encountered, the body’s immediate response is triggered. The adrenal-pituitary-cortex system is activated, leading to the release of hormones that produce the stress response. At this point, the individual is physiologically prepared for fight or flight — a state of high arousal and readiness to confront or escape the threat.
2. Resistance Stage
If the stressor persists beyond the initial alarm, the body enters the resistance stage. Here, the parasympathetic nervous system takes over, calling for a more cautious and economical use of the body’s resources. The organism is no longer in a state of full emergency but is actively making efforts to cope with the threat, often through confrontation or sustained adaptation. The body tries to maintain a level of normal functioning while still dealing with the stressor.
3. Exhaustion Stage
If exposure to the same stressor continues, or if additional stressors are added, the body’s resources become depleted. This leads to the third stage: exhaustion. The physiological systems that were activated during the alarm and resistance stages become ineffective. The body can no longer sustain its adaptive efforts, and the individual becomes more susceptible to stress-related diseases. Conditions such as high blood pressure become more likely at this stage.
A Common Misunderstanding
The exhaustion stage does not mean the person simply feels tired. It refers to the physiological breakdown of the body’s stress-response systems, making the person vulnerable to illness and disease.