fight-or-flight response

physiology

Also known as: defense reaction

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History

fight-or-flight response, response to an acute threat to survival that is marked by physical changes, including nervous and endocrine changes, that prepare a human or an animal to react or to retreat. The functions of this response were first described in the early 1900s by American neurologist and physiologist Walter Bradford Cannon, who also coined the phrase. When a threat is perceived, the sympathetic nerve fibres of the autonomic nervous system are activated. This leads...