Narcolepsy can disrupt sleep.
Sleep . Humans may suffer from various sleep disorders , including dyssomnias , such as insomnia , hypersomnia , narcolepsy , and sleep apnea ; parasomnias , such as sleepwalking and REM behavior disorder ; bruxism ; and circadian rhythm sleep disorders . Sleep onset . Sleep onset usually transmits into non-rapid eye movement sleep ( NREM sleep ) but under certain circumstances ( e.g. narcolepsy ) it is possible to transit from wakefulness directly into rapid eye movement sleep ( REM sleep ) .