Why do we sleep?

Watch as Dr. Michael Breus discusses various reasons why we sleep.


Despite thousands of sleep studies done through the years, we still do not know exactly why we sleep.

Before 1951, scientists believed that sleep was merely the shutdown mode for the mind and body. We did not learn about rapid eye movement (REM) until a University of Chicago graduate student hooked his son up to a brain wave machine while the boy was sleeping.

During REM sleep, our eyes twitch, our facial muscles and limbs may move and we dream.

One theory is that during sleep our brain sorts through the information it received throughout the day and decides what should stick around and where it should be filed. Some goes into specific folders and the rest into our mind's trash bin. Behavior research supports this notion, but sleep is so mysterious and everyone is unique, so it is difficult to be sure.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.