Parasomnias

Parasomnias are defined as unpleasant or undesirable behavioral or experiential phenomena that occur predominately or exclusively during the sleep period. Recent clinical and polygraphic analysis has revealed that they are the result of a large number of completely different conditions, most of which are diagnosable and treatable. The parasomnias may be conveniently categorized as primary (disorders of the sleep states per se) and secondary (disorders of other organ systems, which manifest themselves during sleep). This article focuses on the most common parasomnias: disorders of arousal, the rapid eye movement behavior disorder, and nocturnal seizures.