is a condition characterized by temporary paralysis of the body shortly after waking up (known as hypnopompic paralysis) or, less often, shortly before falling asleep (known as hypnagogic paralysis).
Physiologically, it is closely related to the paralysis that occurs as a natural part of REM (rapid eye movement) sleep, which is known as REM atonia. Sleep paralysis occurs when the brain awakes from a REM state, but the bodily paralysis persists. This leaves the person fully conscious, but unable to move. In addition, the state may be accompanied by terrifying hallucinations (hypnopompic or hypnagogic) which cause an acute sense of danger . Sleep paralysis is particularly frightening to the individual due to the vividness of such hallucinations. The hallucinatory element to sleep paralysis makes it even more likely that someone will interpret the experience as a dream, since completely fanciful, or dream-like, objects may appear in the room alongside one's normal vision. Some scientists have proposed this condition as a theory for alien abductions and ghostly encounters.
The paralysis can last from several seconds to several minutes "after which the individual may experience panic symptoms and the realization that the distorted perceptions were false" . When there is an absence of narcolepsy, sleep paralysis is referred to as isolated sleep paralysis (ISP). "ISP appears to be far more common and recurrent among African Americans than among White Americans or Nigerian Blacks" , and is often referred to within African American communities as "the witch riding your back"
Possible causes
Sleep paralysis occurs during REM sleep, thus preventing the body from manifesting movements made in the subject's dreams. Very little is known about the physiology of sleep paralysis.[citation needed] However, some have suggested that it may be linked to post-synaptic inhibition of motor neurons in the pons region of the brain.[citation needed] In particular, low levels of melatonin may stop the depolarization current in the nerves, which prevents the stimulation of the muscles, to prevent the body from enacting the dream activity (e.g. preventing a sleeper from flailing his legs when dreaming about running).[citation needed]
Several studies have concluded that many or most people will experience sleep paralysis at least once or twice in their lives.[citation needed]
Many people who commonly enter sleep paralysis also suffer from narcolepsy. In African-Americans, panic disorder occurs with sleep paralysis more frequently than in Caucasians.[10] Some reports read that various factors increase the likelihood of both paralysis and hallucinations. These include:[11]
* Sleeping in an upwards supine position
* Irregular sleeping schedules; naps, sleeping in, sleep deprivation
* Increased stress
* Sudden environmental/lifestyle changes
* A lucid dream that immediately precedes the episode.
ini penjelasannya semoga membantu translate sendiri yah...
), eh si artis bener2 kayak keliatan...
