Abstract
Non-REM (NREM) parasomnias comprise abnormal sleep-related behaviors, autonomic nervous
system function, and emotional experiences that typically arise out of deep NREM sleep.
Categorized broadly as disorders of arousal (DoA), confusional arousals (CoA), sleepwalking
(SW), and sleep terrors (ST) share common pathophysiological mechanisms and contributing
factors. Sexsomnia is classified as a variant of CoA and SW, while sleep-related eating
disorder is classified as a separate NREM parasomnia. These parasomnias emerge due
to incomplete dissociation of wakefulness from NREM sleep, resulting in partial arousal
characterized by decreased consciousness during motor and emotional manifestations.
The behaviors emerge as a result of the interplay of various predisposing and priming
factors with the additional layer of precipitating conditions. Cyclic alternating
patterns and abnormal slow wave synchronization increase susceptibility to developing
these behaviors in the background of genetic predisposition. We will discuss current
diagnostic criteria, differential diagnoses, implications, and management of these
parasomnias. Recent scientific developments in this area will be discussed, especially
in reference to etiopathogenesis and treatment strategies of lesser-studied subtypes
such as sexsomnia. The mainstay of treatment comprises alleviating the contributing
factors and treating any comorbid sleep disorders that may curtail sleep duration
and also increase abnormal arousal. Behavioral interventions can be beneficial, although
sometimes less established pharmacotherapy is also utilized.
Keywords non-REM parasomnias - sleepwalking - sleep terrors - sleep-related eating disorder
- confusional arousals - sexsomnia - disorders of arousal - somnambulism
