[Parasomnia].

The parasomnias comprises a group of disorders that intrude into the sleep process and are not primarily disorders of sleep and wake states per se. These disorders are manifestations of central nervous system activation usually transmitted through skeletal muscle or autonomic nervous system channels (ICSD 1990). The parasomnias are divided into four groups: Arousal disorders (sleepwalking, night terrors, and confusionnal arousal), sleep-wake transition disorders (rhythmic movement disorder, sleep starts), REM sleep parasomnias (nightmares, sleep paralysis, hallucinations, and REM sleep behavior disorders), and other parasomnias (sleeptalking, nocturnal enuresis, and nocturnal bruxism.