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Non-24-hour sleep-wake syndrome following a car accident
D B Boivin1, F O James, J B Santo
1Center for Study and Treatment of Circadian Rhythms, Douglas Hospital Research Center, Verdun, Quebec, Canada. boidia@douglas.mcgill.ca
Abstract:
The authors report the case of a 39-year-old sighted woman who displayed non-24-hour sleep-wake cycles following a car accident. The phase relationship between endogenous circadian markers such as plasma melatonin and 6-sulfatoxymelatonin rhythms and self-selected sleep times was abnormal. A laboratory investigation indicated that she was sensitive to bright light as a circadian synchronizer. MRI and brain CT scans were normal, but microscopic brain damage in the vicinity of the suprachiasmatic nucleus or its output pathways is plausible.
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