Non–24-hour sleep–wake rhythm disorder in sighted and blind patients
M Uchiyama, SW Lockley - Sleep Medicine Clinics, 2015 - sleep.theclinics.com
Non–24-hour sleep–wake rhythm disorder (N24SWD) is defined as a “history of insomnia,
excessive daytime sleepiness, or both, which alternate with asymptomatic episodes, owing
to misalignment between the light-dark cycle and the non-entrained endogenous circadian
rhythm of sleep-wake propensity.” 1, 2 The daily light–dark cycle is the most powerful
environmental time cue for synchronizing the hypothalamic circadian pacemaker to the 24-
hour day. Individuals who are physically or biologically isolated from a normal 24-hour light …
excessive daytime sleepiness, or both, which alternate with asymptomatic episodes, owing
to misalignment between the light-dark cycle and the non-entrained endogenous circadian
rhythm of sleep-wake propensity.” 1, 2 The daily light–dark cycle is the most powerful
environmental time cue for synchronizing the hypothalamic circadian pacemaker to the 24-
hour day. Individuals who are physically or biologically isolated from a normal 24-hour light …