fight or flight response

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Related to fight or flight response: General adaptation syndrome

fight or flight re·sponse

a theory advanced by Walter B. Cannon, according to which animal and human organisms in situations requiring that they either fight or flee are provided with a check-and-drive mechanism that puts them in readiness to respond with undivided energy output; the mechanism is characterized by increased sympathetic nervous system activity, including increased catecholamine production with associated increases in blood pressure, heart and respiratory rates, and skeletal muscle blood flow. Thus an internal reaction makes possible external behavior in response to danger.
See also: relaxation response. Compare: alarm reaction.
References in periodicals archive ?
Our study was the first to examine the role of a dysfunctional fight or flight response in depression in a large population.
The accelerated heart rates of the students repeating the swear word may indicate an increase in aggression, in a classic fight or flight response of downplaying feebleness in favour of a more pain-tolerant machismo.
The fight or flight response is an important mechanism in an emergency, like being chased by a tiger.