Sleep Paralysis

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Related to Sleep Paralysis: Lucid Dreaming

sleep paralysis

[′slēp pə‚ral·ə·səs]
Transient paralysis with spontaneous recovery occurring on falling asleep or on awakening.

Sleep Paralysis (Sleep Immobility)


Most people have had the experience of not being able to move in a dream. Being unable to run away from some kind of danger—or trying to run and being able to move only very slowly—is particularly common because at some level we know that we are paralyzed when we dream. During the rapid eye movement (REM) stage of sleep, when our most active dreams occur, a relay station at the top of the spinal column disconnects the motor cortex from the rest of the body, with the exception of the lungs and the eyes. This is why the neck muscles lose their tone during this stage, which is one of the defining characteristics of REM sleep.

Clearly this is a biological mechanism for preventing us from awakening otherwise we might thrash about during dreams. This disconnection of the motor impulses is the reason sleepwalking occurs only during non-REM sleep. It is also a factor in the sleep disorder referred to as sleep paralysis (which is distinct from normal REM sleep immobility), in which the sleeper is completely paralyzed immediately before entering (and sometimes immediately after leaving) sleep.

References in periodicals archive ?
Najma Firas, 20, a Libyan-American student, said she experiences sleep paralysis about four nights a night.
Several categories are prescribed to treat cataplexy, hypnagogic hallucinations and sleep paralysis.
I realized that there were no real sleep paralysis prevalence rates available that were based on large and diverse samples," Sharpless said.
The tetrad of EDS, cataplexy, sleep paralysis, and hallucinations is the hallmark of narcolepsy, though not all of the symptoms need be present (Table I).
SLEEP paralysis is a condition that strikes a person who is most often in a supine position and is about to drop off to sleep, or has just woken up, and realises that he or she is unable to move, speak, or cry out.
Hypnagogic and hypnopompic hallucinations are often associated with sleep paralysis.
Sleep paralysis is caused by a biological function that has evolved to prevent our body moving around and causing physical injury while we are dreaming.
8) Patients interpret sleep paralysis experiences in subjective terms.
Introduction: Sleep paralysis is a conscious state body immobilization event that appears spontaneously or secondarily to stress situations or to possible bad quality of dream.
Despite the social taboo surrounding it, these experiences are actually symptomatic of an extremely widespread sleeping condition known as Isolated Sleep Paralysis (ISP), which can start at any time ( usually during the teenage years) and declines sharply during the late 20s.