Sleep paralysis

[[File:Cat napping.jpg|thumb|right|165px|[[Cat|One common cause of sleep paralysis]]]]
{{psychology}}
'''Sleep paralysis''' is a condition that occurs when there is an ill-timed disconnection between the [[brain]] and the body when coming into or going out of [[sleep]] (hypnagogia).<ref>[http://www.medterms.com/script/main/art.asp?articlekey=9806 Medical Definition of Sleep paralysis] ''MedicineNet''.</ref> This results in the sufferer finding themselves unable to move for a few seconds or several minutes, and occasionally longer.

==Causes==
[[Image:John Henry Fuseli - The Nightmare.JPG|thumb|left|According to Wikipedia, sleep paralysis makes demons squat on the chests of beautiful women.{{fact|joke}}]]
Sleep paralysis strikes most often as a person is moving into or out of REM sleep. This is the deepest part of the sleep cycle, during which the body is disconnected from the brain, in order to prevent the dreamer physically acting out their dreams. This does, however, leave the body paralysed. 

Sleep paralysis is being studied as an explanation for terrors in the night, as many people who have experienced the phenomenon report feeling a "presence" that is often described as malevolent, threatening, or evil. An intense sense of dread and terror is very common. The presence is likely to be vaguely felt or sensed just out of sight but thought to be watching or monitoring, often with intense interest, sometimes standing by, or sitting on, the bed.<ref>[https://web.archive.org/web/20080310210918/http://watarts.uwaterloo.ca/~acheyne/S_P2.html/ Sleep Paralysis and Associated Hypnagogic and Hypnopompic Experiences] ''University of Waterloo'' (archived from March 10, 2008).</ref>

==Supernatural interpretations==
Although the physical effects of sleep paralysis rarely last more than a few moments, the memories of the frightening sensations felt during an attack can last long after the episode. It is believed that sleep paralysis accounts for some (or all) of the old claims of attacks by [[witch]]es, manifestations by [[ghost]]s, and the more recent "reports" of [[Alien abduction|nocturnal abduction]] by [[Extraterrestrial|space aliens]], e.g., as in the case of [[Whitley Strieber]]'s book ''Communion''.<ref>''The Skeptic's Guide to the Universe'' by Steven Novella (2018) Grand Central Publishing. ISBN 1538760517.</ref>{{rp|38-39}}

Sleep paralysis goes by many names, including the "old hag" in [[Newfoundland and Labrador|Newfoundland]], based on the myth of an old witch who would sit on the chest of the victim. In the West Indies, it's "kokma", named for a ghostly baby who jumps on the sleeper's chest and attacks the throat. In [[China]] and [[Japan]], it's "ghost pressure" (鬼压床 ''guǐ yā chuáng'', or 金縛り ''kanashibari'', respectively), because a ghost sits on the sleeper's chest and assaults the sleeper. In [[Medieval]] [[Europe]], demons called [[Incubus and succubus myths|incubus and succubus]] were said to attack women and men, respectively, usually sexually.

==See also==
*[[Ghosts]]
*[[Alien abduction]]
*[[Incubus and succubus myths]]
*[[Lucid dream]]
*[[Shadow people]]

==External links==
*[http://watarts.uwaterloo.ca/~acheyne Waterloo University's coverage of sleep paralysis]
*[http://www.wikihow.com/Cope-with-Sleep-Paralysis How to cope with sleep paralysis]

==References==
{{Reflist}}

[[Category:Psychology]]
[[Category:Medicine]]
[[Category:Sleep]]
[[Category:Horror]]

Categories: Psychology, Medicine, Sleep, Horror