LAUSR

The elucidation of the science of sleep and its attendant disorders has been explosive over the past 40 years, particularly since the development of positive airway pressure for the treatment of obstructive sleep apnea syndrome in the early 1980s and the discovery of the CNS excitatory peptides, Hypocretin/Orexin in 1998. The nosology of sleep disorders has also changedwith an emphasis on the presumed etiologic factors of the different clinical syndromes. This is most evident in the knowledge base and treatment regimens of disorders of central hypersomnolence. Narcolepsy with cataplexy (themost well-known disorder in this group, with a presumed etiology of the loss of, or substantial reduction in, hypocretin/orexin cells in the postero-lateral hypothalamus) is now designated Narcolepsy Type 1. It is defined as daily periods of irrepressible need to sleep or daytime lapses (excessive daytime sleepiness or EDS) into sleep for ≥3 months and one must have one or both of the following: