The Sleep-Paralysis Phenomenon

It sounds like something out of a sci-fi film, but paralysis resulting from a temporary disconnection of the body from the brain is a fairly common sleep disorder. Although it is considered harmless, and even normal, by sleep experts, it can be terrifying for those who are afflicted.

What It Feel Like

It only lasts for about a minute, but during sleep paralysis, you cannot move your head or body, and you cannot speak. You can breathe, and you may be able to move your eyes slightly. Although they do not occur in all cases of sleep paralysis, hallucinations are a trademark side effect, or accompanying symptom. There may be a physical sense of someone or something sitting on your chest or otherwise touching you. You may hear voices and you may also feel as though you are floating or flying above your bed.

Why It Happens

The reason sleep paralysis is considered normal is because it occurs during the REM (rapid eye movement) stage of sleep, when the body and brain are essentially in the sense that the body is not receiving signals or direction from the brain. This disassociation serves a real purpose during normal sleep. It prevents us from acting out physical movements in our dreams so we don't fall out of bed or hurt our sleep partners or ourselves. During REM sleep is also when we experience our most intense and vivid dreams. Although no one knows exactly why sleep paralysis occurs, it is thought to be an extension of this state.

Who It Affects

Sleep paralysis is often associated with narcolepsy, a condition that causes people to fall asleep suddenly and often, can include a paralysis effect, and is also associated with abnormalities in REM sleep. People who do not have narcolepsy, however, also experience sleep paralysis. And unlike narcolepsy, which is associated with falling asleep, sleep paralysis is associated with the wakening stages of sleep.

How You Can Prevent It

Although isolated incidents of sleep paralysis are fairly common, ongoing episodes throughout a lifetime are rare.  According to researchers at the Sleep Disorders Center in the Department of Neurology at Louisiana State University, avoiding sleep deprivation, stress and sleep interruption are the best ways to avoid an incident of sleep paralysis. Since these conditions are often associated with anxiety and depression, medication such as SSRIs (selective serotonin reuptake inhibitors) are sometimes prescribed.


Katz, Hila. "Sleep Paralysis." Columbia Science Review. Spring 2005. Web. 30 Oct 2010.

McCarty, DE and Chesson, AL. "A Case of Sleep Paralysis with Hypnopompic Hallucinations." Journal of Clinical Sleep Medicine. 15 Feb 2009; 5(1):83-84. Web. 30 Oct 2010.