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Sleeplessness and Circadian Rhythm Disorder Topic Guide

Sleeplessness and Circadian Rhythm Disorder Sleeplessness and Circadian Rhythm Disorder:

A person's circadian rhythm is an internal biological clock that regulates a variety of biological processes according to an approximate 24-hour period. A disorder of the circadian rhythm may cause sleeplessness on at transient or chronic basis. The disorder can be caused by air travel across time zones, shift work, irregular sleep-wake cycle, delayed sleep phase syndrome, and advanced sleep-phase syndrome.

Sleeplessness and Circadian Rhythm Disorder Topic Guide - Visuals