where is fight or flight in the brain
the adrenal medulla
title: Fight-or-flight response text: Fight-or-flight response The fight-or-flight 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. It was first described by Walter Bradford Cannon. His theory states that animals react to threats with a general discharge of the sympathetic nervous system, preparing the animal for fighting or fleeing. More specifically, the adrenal medulla produces a hormonal cascade that results in the secretion of catecholamines, especially norepinephrine and epinephrine. The hormones estrogen, testosterone, and cortisol, as well as the neurotransmitters dopamine and serotonin, also affect how title: Startle response text: of the stria terminalis (BNST) and anterior cingulate cortex are all thought to play a role in modulating the reflex. The anterior cingulate cortex in the brain is largely thought to be the main area associated with emotional response and awareness, which can contribute to the way an individual reacts to startle inducing stimuli. Along with the anterior cingulate cortex, the amygdala and the hippocampus are known to have implications in this reflex. The amygdala is known to have a role in the “fight or flight” response, and the hippocampus functions to form memories of the stimulus and the emotions title: Freezing behavior text: to cause changes such as shortness of breath, increased heart rate, sweating, or choking sensation. However, since it is difficult to measure these sympathetic responses to fear stimuli, studies are typically confined to simple crouching times. A response to stimuli typically is said to be a "fight or flight", but is more completely described as "fight, flight, or freeze." In addition, freezing is observed to occur before or after a fight or flight response. Studies suggest that specific areas of the brain are known to either elicit (or inhibit in the case of lesions) freezing behavior in subjects. The regions title: Norepinephrine text: noradrenergic. The general function of norepinephrine is to mobilize the brain and body for action. Norepinephrine release is lowest during sleep, rises during wakefulness, and reaches much higher levels during situations of stress or danger, in the so-called fight-or-flight response. In the brain, norepinephrine increases arousal and alertness, promotes vigilance, enhances formation and retrieval of memory, and focuses attention; it also increases restlessness and anxiety. In the rest of the body, norepinephrine increases heart rate and blood pressure, triggers the release of glucose from energy stores, increases blood flow to skeletal muscle, reduces blood flow to the gastrointestinal system, and title: Fight-or-flight response text: that occur during the fight-or-flight response. This component of the autonomic nervous system utilises and activates the release of norepinephrine in the reaction. The parasympathetic nervous system originates in the sacral spinal cord and medulla, physically surrounding the sympathetic origin, and works in concert with the sympathetic nervous system. Its main function is to activate the "rest and digest" response and return the body to homeostasis after the fight or flight response. This system utilises and activates the release of the neurotransmitter acetylcholine. The reaction begins in the amygdala, which triggers a neural response in the hypothalamus. The initial reaction