Parasomnias: sleep disturbances with automatic behaviors

According to the present International Classification of Sleep Disorders (ICSD-2) parasomnias are defined as undesirable clinical disorders, associated with physical events or experiences occurring during entry into sleep, within sleep and during arousal from sleep. The clinical spectrum of parasomnias encompasses abnormal sleep-related movements, behaviors, emotions, perceptions, dreaming and autonomic nervous system activation. Parasomnia behaviors are to be considered as automatisms, motor acts unconscious and uncontrolled by volition. Parasomnias disrupt sleep and may have adverse health and psychosocial effects. Pathophysiologically these sleep disorders may be explained as dissociations between the three primary states of wakefulness, NREM sleep and REM sleep. In the ICSD-2 many categories of parasomnias are reported. We will describe the main parasomnias arising from NREM as well as REM sleep.