physiology of stress: GAS model Flashcards
how did Selye view stress?
the body’s attempt to adapt to any stressor
what are the 3 stages of GAS?
- alarm reaction
- resistance
- exhaustion
when a stressor is perceived, what is the immediate physiological response?
shock
what happens during shock in the alarm reaction stage?
the body’s resources are briefly decreased (e.g. resistance is lowered) before quickly recovering
how does the body attempt to adapt to the stressful environmental demands?
by resisting the stressor
how is physiological activity in the resistance stage?
greater than normal + uses a lot of energy
what happens to the body’s resources during the second stage?
they are being consumed at a potentially harmful rate (e.g. stress hormones are produced in large quantities + will soon be depleted)
why is the parasympathetic nervous system activated?
to conserve energy for the longer term, because the stressor is becoming chronic
what does the individual experience in the exhaustion stage?
they re-experience symptoms of sympathetic arousal that first appeared in the alarm stage (e.g. sweating, raised heart rate, etc.)
what happens to the body’s resources in the third stage?
they have become drained, so resistance plummets
in what stage are stress-related illnesses likely?
exhaustion stage/third stage
name one strength of GAS
there is research support
what was Selye’s procedure + findings? (research support)
~ he subjected rats to various physical stressors (e.g. extreme cold, surgical injury)
~ he found that the same collection of responses occurred regardless of the stressor
name one limitation of GAS
it may not be general
what was Mason’s procedure + findings? (counterpoint to Selye)
~ he replicated Selye’s procedure using monkeys, measuring responses to 7 different stressors by measuring levels of urinary cortisol
~ he found that outcomes depended on the stressor (e.g. extreme cold increased cortisol levels whereas extreme heat reduced them)
