Fight-or-flight response

Physiological reaction to a perceived threat or harmful event

The fight-or-flight or the fight-flight-or-freeze response, also known as hyperarousal or acute stress response, is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. It was first described by Walter Bradford Cannon in 1914 which he referred to as "the necessities of fighting or flight" in 1915. His theory states that animals react to threats with a general discharge of the sympathetic nervous system, preparing the animal for fighting or fleeing.

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