title: Circadian rhythm sleep disorders and phototherapy.
abstract: Circadian rhythm sleep disorders are characterized by a desynchronization between the timing of the intrinsic circadian clock and the extrinsic light-dark and social/activity cycles resulting in symptoms of excessive sleepiness and insomnia. This article explores the six recognized circadian rhythm sleep disorders: delayed sleep phase syndrome, advanced sleep phase syndrome, non-24-hour sleep-wake syndrome, irregular sleep-wake pattern, shift work sleep syndrome, and time zone change syndrome. Additionally discussed are the therapeutic roles of synchronizing agents, such as light and melatonin.
authors.affiliation: Department of Neurology, Northwestern University Feinberg School of Medicine, Abbott Hall, Chicago, IL 60611, USA.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Fahey
authors.forename: Phyllis C
authors.initials: PC
authors.lastname: Zee
mesh_terms: D006801:Humans; D020179:Jet Lag Syndrome / Q000628:therapy; D010789:Phototherapy / Q000379:methods*; D020178:Sleep Disorders, Circadian Rhythm / Q000628:therapy*