Hypocretin system plays a critical role in which of the following disorders?

Ans. D. NarcolepsyIt has become apparent that the hypo cretin system plays a critical role in narcolepsy. Narcolepsy is the prototypical example of sleepiness produced by a basic central nervous system dysfunction of sleep mechanisms. The etiology stems from a genetically triggered hypo cretin dysfunction and deficit. Insomnia is defined as difficulty initiating sleep or maintaining sleep or having nonrestorative sleep for 1 month or more. The insomnia or resulting sleepiness must cause clinically significant impairment or distress. To qualify as primary insomnia, the etiology must not be rooted in psychiatric conditions, parasomnias, substance use or abuse, sleep-disordered breathing, or circadian rhythm disorders.