Exploring comorbid sleep disorders in psychiatric
There are two types of sleep: non-rapid eye-movement (NREM) sleep and rapid eye-movement (REM) sleep. Over the course of a sleep period, NREM and REM sleep alternate cyclically.2 This basic structural organization is referred to as sleep architecture.
Two major processes – homeostatic drive and circadian rhythm, regulate the sleep-wake system. Homeostatic drive determines how much sleep is needed, and the circadian rhythm optimizes the ability to achieve that sleep at night.1-2