Nervous System

Sleep and Dreams

When does dreaming occur during the sleep cycle?

Almost all dreams occur during REM sleep. Scientists do not understand why dreaming is important, one theory is that the brain is either cataloging the information it acquired during the day and discarding the data it does not want, or is creating scenarios to work through situations causing emotional distress. Regardless of its function, most people who are deprived of sleep or dreams become disoriented, unable to concentrate, and may even have hallucinations.


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