When do nightmares occur?
Sleep is divided into two types: rapid eye movement (REM) and nonrapid eye movement (non-REM). REM and non-REM sleep alternate in 90- to 100-minute cycles. Most dreaming occurs during REM sleep. Nightmares usually occur in the middle of the night or early morning, when REM sleep and dreaming are more common.
More Answers On Sleep Disorders
- What’s a sleep study?
- What kind of a sleep study is a diagnostic overnight polysomnogram (PSG)?
- What kind of a sleep study is a diagnostic daytime multiple sleep latency test (MSLT)?
- As far as a sleep study, what happens in 2-night evaluation polysomnogram (PSG) and continuous positive airway pressure (CPAP) titration?
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