Sleep is the physiological process whereby the brain achieves rest. The reason for the body’s need for sleep is not fully understood. Sleep symptoms include insomnia (difficulty falling asleep and/or difficulty staying asleep), sleepiness/drowsiness, sleep attacks, somnolence, and other symptoms. Sleep disorders include Obstructive Sleep Apnea (OSA), Chronic Insomnia, Narcolepsy, and many others.

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Why we sleep remains something of a mystery. Dr. Michael Twery, director of the National Center on Sleep Disorders Research at NIH’s National Heart, Lung and Blood Institute, says, “Sleep originates with the timing of our biological clock. The biological clock operates in almost all of our tissues.” A particular region of the brain called the suprachiasmatic nucleus, he says, operates as the master biological clock. It orchestrates what Twery calls a “symphony” of hormones and other changes that prepare our body for sleep.

It’s clear that our body needs this sleep, because of what happens when we don’t get enough of it.

Source: NIH News in Health (NIH)1

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Sleep: A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility.2

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  1. Source: NIH News in Health (NIH): 2007/ April/ docs/ 01features_01.htm
  2. Source: MeSH (U.S. National Library of Medicine)
  3. Source: CDC: sleep/ about_sleep/ key_disorders.html

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Note: This site is for informational purposes only and is not medical advice. See your doctor or other qualified medical professional for all your medical needs.