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Heart Rhythm (fight or flight)

Abusive relationships change the physiology of the brain. #cptsd

The fight-or-flight or the fight-flight-or-freeze response (also called hyperarousal or the acute stress response) is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival.[1] It was first described by Walter Bradford Cannon.[a][2] His theory states that animals react to threats with a general discharge of the sympathetic nervous system, preparing the animal for fighting or fleeing.[3] More specifically, the adrenal medulla produces a hormonal cascade that results in the secretion of catecholamines, especially norepinephrine and epinephrine.[4] The hormones estrogen, testosterone, and cortisol, as well as the neurotransmitters dopamine and serotonin, also affect how organisms react to stress.[5] The hormone osteocalcin might also play a part.[6][7]

What Happens During the Fight-or-Flight Response

In the 1920s, American physiologist Walter Cannon was the first to describe the fight-or-flight response. Cannon realized that a chain of rapidly occurring reactions inside the body helped to mobilize the body's resources to deal with threatening circumstances.

Today, the fight-or-flight response is recognized as part of the first stage of Hans Selye's general adaptation syndrome (a theory describing the stress response).1

In response to acute stress, the body's sympathetic nervous system is activated by the sudden release of hormones. The sympathetic nervous system then stimulates the adrenal glands, triggering the release of catecholamines (including adrenaline and noradrenaline).

This chain of reactions results in an increase in heart rate, blood pressure, and breathing rate. After the threat is gone, it takes between 20 to 60 minutes for the body to return to its pre-arousal levels.