Diagnostic Tools for Parasomnias

Abstract

Parasomnias are abnormal behavioral or physiological events that intrude into the sleep process, disrupting its continuity. Parasomnias are classified according to the type of sleep in which they occur, namely non-rapid eye movement (NREM) and rapid eye movement (REM) sleep parasomnias (1). The first includes disorders of arousals, namely confusional arousals (and their recently identified variants of sleep-related abnormal sexual behaviors), sleep terrors, and sleepwalking. REM sleep parasomnias include REM sleep behavior disorder, recurrent isolated sleep paralysis, and nightmare disorders. Other parasomnias include sleep enuresis, sleep-related groaning, exploding head syndrome, sleep-related hallucinations, and sleep-related eating disorder. The latter shares many features with the disorders of arousals, being frequently associated to sleepwalking. Hence, parasomnias comprise a variety of abnormal sleep-related movements, behaviors, emotions, dreaming, and autonomic phenomena that emerge from sleep as an expression of an anomalous central nervous system activation during sleep.