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 ?
However, as a number of participants in the present study discussed negative emotions in terms of fear and confusion, some of these cases could be related to sleep paralysis rather than anxiety.
GHB treatment has a high rate of success in reducing cataplexy, sleep attacks, sleep paralysis, and hypnagogic hallucinations.
But other people enjoy the sensations they feel during sleep paralysis.
Sleep paralysis occurs as a patient with narcolepsy is either falling asleep or awakening.
WHAT happened to Manish might sound like its straight out of a horror movie, but is in fact a real health problem called sleep paralysis (SP).
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.
Like sleep paralysis, they are common in people with narcolepsy but can also occur in those with no identified sleep disorder.
With abduction cases, there are psychological explanations such as vivid dreams or sleep paralysis,but again there is a small hard core of cases which are extremely interesting.
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.
Many of the classic symptoms of narcolepsy, such as excessive daytime sleepiness, cataplexy, sleep paralysis, and hypnagogic hallucinations, may be mistakenly associated with other disease states and must be differentiated from other sleep disorders.
Symptoms of narcolepsy include excessive daytime sleepiness (even dropping off to sleep at any time, whether it be watching TV or driving a car), cataplexy (brief episodes of muscle weakness brought on by strong emotion), sleep paralysis (inability to move occurring at the moment of failing asleep), and hypnagogic hallucinations (dreamlike images that occur at sleep onset).
9] Besides excessive daytime sleepiness (EDS) and uncontrollable sleep attacks, the classic symptoms of narcolepsy include: cataplexy (short episodes of muscle weakness and/or paralysis without change in consciousness that are precipitated by strong emotion); sleep paralysis (the inability to move muscles while falling asleep or on awakening); and hypnagogic or hypnopompic hallucinations (dreamlike images occurring at sleep onset or on awakening, respectively).