General Adaptation Syndrome (GAS) - Selye, 1936;1983

The General Adaptation Syndrome

= the body’s typical response pattern in terms of resistance to stress over time. Selye proposed that a bodily mechanism called ‘adaptation’ was required to respond to both eustress and distress.

GAS Model

= used to describe the physiological changes/response that the body automatically goes through in an attempt to alleviate the impact of any stressor (real or imagined, eustress or distress, internal or external).

3 Stages of the Model

Alarm, Resistance and Exhaustion.

Alarm Stage

= the initial response to a stressor (generally defensive).

The Shock Stage (substage of Alarm)

= (during/after exposure to stressor) stress resistance falls below normal levels and body acts as though injured.

The Counter-shock stage (substage of Alarm)

= the sympathetic nervous system is activated and the body’s resistance to the stressor increases. Fight or flight response. Physical effects of shock momentarily reduce the ability to deal with stressors.

Resistance Stage

= if the stressor remains, the body enters the state of reisistance, it will not receive a clear signal to return to normal functioning levels and will attempt to adapt. The body will be better prepared to cope with the stressor as the physiological arousal remains higher and the body strives to reach equilibrium. Immune system is suppressed and the body is more susceptible to ‘wear and tear’.

Exhaustion Stage

= where the body’s physical, emotional and mental resources are depleted to the point where the body no longer has strength to fight the stress. Occurs if the stressor is severe and chronic, so the body is unable to adapt and return to normal levels during the resistance phase. Hormonal activity increases, along with increased circulation of cortisol, which increases vulnerability to illness, anxiety and irritability which can lead to chronic fatigue, burnout and other disorders.

Strengths of the GAS Model

• supported by empirical evidence

• first to highlight that stress has a major impact on the immune system

Limitations of the GAS Model

• too much emphasis on the biology of the stress response

• doesn’t take into account psychological factors that explain individuals’ stress experiences

• research is based on animals, therefore not generalizable to humans

• assumes that the stress response is physiologically uniform