Changes

==Origin==

==Origin==

Middle French choc, from choquer to strike against, from Old French choquier, probably of Germanic origin; akin to Middle Dutch schocken to jolt

Middle French choc, from choquer to strike against, from Old French choquier, probably of Germanic origin; akin to Middle Dutch schocken to jolt

*[http://en.wikipedia.org/wiki/16th_century 1565]

*[https://en.wikipedia.org/wiki/16th_century 1565]

==Definitions==

==Definitions==

*1: the impact or encounter of [[individuals]] or [[groups]] in combat

*1: the impact or encounter of [[individuals]] or [[groups]] in combat

Acute [[stress]] [[reaction]] (also called acute stress disorder, psychological '''shock''', mental shock, or simply, shock) is a [[psychological]] condition arising in [[response]] to a terrifying or traumatic [[event]]. It should not be [[confused]] with the unrelated circulatory condition of shock.

Acute [[stress]] [[reaction]] (also called acute stress disorder, psychological '''shock''', mental shock, or simply, shock) is a [[psychological]] condition arising in [[response]] to a terrifying or traumatic [[event]]. It should not be [[confused]] with the unrelated circulatory condition of shock.

"Acute stress response" was first described by [http://en.wikipedia.org/wiki/Walter_Cannon Walter Cannon] in the 1920s as a [[theory]] that [[animals]] react to threats with a general discharge of the sympathetic [[nervous system]]. The [[response]] was later recognized as the first stage of a general adaptation syndrome that regulates stress responses among vertebrates and other [[organisms]].

"Acute stress response" was first described by [https://en.wikipedia.org/wiki/Walter_Cannon Walter Cannon] in the 1920s as a [[theory]] that [[animals]] react to threats with a general discharge of the sympathetic [[nervous system]]. The [[response]] was later recognized as the first stage of a general adaptation syndrome that regulates stress responses among vertebrates and other [[organisms]].

The onset of a [[stress]] response is associated with specific physiological [[actions]] in the sympathetic [[nervous system]], both directly and indirectly through the release of [http://en.wikipedia.org/wiki/Epinephrine epinephrine] and to a lesser extent [http://en.wikipedia.org/wiki/Norepinephrine norepinephrine] from the [http://en.wikipedia.org/wiki/Adrenal_medulla medulla] of the [http://en.wikipedia.org/wiki/Adrenal_glands adrenal glands]. The release is triggered by [http://en.wikipedia.org/wiki/Acetylcholine acetylcholine] released from pre-[http://en.wikipedia.org/wiki/Ganglion ganglionic] sympathetic nerves. These catecholamine [[hormones]] facilitate immediate [[physical]] reactions by triggering increases in heart rate and [[breathing]], constricting blood vessels in many parts of the [[body]]—but not in muscles (vasodilation), brain, lungs, and heart—and tightening muscles. An [[abundance]] of catecholamines at neuroreceptor sites facilitates reliance on [[spontaneous]] or [[intuitive]] [[behaviors]] often related to combat or [[escape]].

The onset of a [[stress]] response is associated with specific physiological [[actions]] in the sympathetic [[nervous system]], both directly and indirectly through the release of [https://en.wikipedia.org/wiki/Epinephrine epinephrine] and to a lesser extent [https://en.wikipedia.org/wiki/Norepinephrine norepinephrine] from the [https://en.wikipedia.org/wiki/Adrenal_medulla medulla] of the [https://en.wikipedia.org/wiki/Adrenal_glands adrenal glands]. The release is triggered by [https://en.wikipedia.org/wiki/Acetylcholine acetylcholine] released from pre-[https://en.wikipedia.org/wiki/Ganglion ganglionic] sympathetic nerves. These catecholamine [[hormones]] facilitate immediate [[physical]] reactions by triggering increases in heart rate and [[breathing]], constricting blood vessels in many parts of the [[body]]—but not in muscles (vasodilation), brain, lungs, and heart—and tightening muscles. An [[abundance]] of catecholamines at neuroreceptor sites facilitates reliance on [[spontaneous]] or [[intuitive]] [[behaviors]] often related to combat or [[escape]].

Normally, when a [[person]] is in a serene, unstimulated state, the "firing" of [[neurons]] in the [http://en.wikipedia.org/wiki/Locus_ceruleus locus ceruleus] is minimal. A novel stimulus, once perceived, is relayed from the [http://en.wikipedia.org/wiki/Sensory_cortex sensory cortex] of the [[brain]] through the [http://en.wikipedia.org/wiki/Thalamus thalamus] to the [http://en.wikipedia.org/wiki/Brain_stem brain stem]. That route of signaling increases the rate of noradrenergic activity in the locus ceruleus, and the [[person]] becomes alert and [[attentive]] to the [[environment]].

Normally, when a [[person]] is in a serene, unstimulated state, the "firing" of [[neurons]] in the [https://en.wikipedia.org/wiki/Locus_ceruleus locus ceruleus] is minimal. A novel stimulus, once perceived, is relayed from the [https://en.wikipedia.org/wiki/Sensory_cortex sensory cortex] of the [[brain]] through the [https://en.wikipedia.org/wiki/Thalamus thalamus] to the [https://en.wikipedia.org/wiki/Brain_stem brain stem]. That route of signaling increases the rate of noradrenergic activity in the locus ceruleus, and the [[person]] becomes alert and [[attentive]] to the [[environment]].

If a [[stimulus]] is perceived as a threat, a more [[intense]] and prolonged discharge of the locus ceruleus activates the sympathetic division of the [http://en.wikipedia.org/wiki/Autonomic_nervous_system autonomic nervous system] (Thase & Howland, 1995). The activation of the sympathetic [[nervous system]] leads to the release of norepinephrine from nerve endings acting on the [[heart]], blood vessels, respiratory centers, and other sites. The ensuing physiological changes constitute a major part of the acute stress response. The other major player in the acute stress response is the [http://en.wikipedia.org/wiki/Hypothalamic-pituitary-adrenal_axis hypothalamic-pituitary-adrenal axis].[http://en.wikipedia.org/wiki/Acute_stress_reaction]

If a [[stimulus]] is perceived as a threat, a more [[intense]] and prolonged discharge of the locus ceruleus activates the sympathetic division of the [https://en.wikipedia.org/wiki/Autonomic_nervous_system autonomic nervous system] (Thase & Howland, 1995). The activation of the sympathetic [[nervous system]] leads to the release of norepinephrine from nerve endings acting on the [[heart]], blood vessels, respiratory centers, and other sites. The ensuing physiological changes constitute a major part of the acute stress response. The other major player in the acute stress response is the [https://en.wikipedia.org/wiki/Hypothalamic-pituitary-adrenal_axis hypothalamic-pituitary-adrenal axis].[https://en.wikipedia.org/wiki/Acute_stress_reaction]

[[Category: Health]]

[[Category: Health]]

[[Category: Biology]]

[[Category: Biology]]