Fight-or-flight response

Definition

The fight-or-flight response is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. It triggers a chain of rapid changes within the body, such as increased heart rate and adrenaline release, preparing an individual for either confronting the threat or fleeing from it.

Related terms

Autonomic Nervous System: The part of the nervous system responsible for control of bodily functions not consciously directed, such as breathing, the heartbeat, and digestive processes.

Adrenaline: A hormone secreted by the adrenal glands that increases rates of blood circulation, breathing, and carbohydrate metabolism and prepares muscles for exertion.

Sympathetic Nervous System: A division of the autonomic nervous system that activates what is often termed the fight or flight response