CHRONOBIOLOGICAL ASPECTS OF NARCOLEPSY

The circadian, circasemidian and ultradian features of sleep-wake patt erns in narcolepsy are reviewed with respect to the hypotheses that ch ronobiological disturbances might either be specific to the condition or contribute to its symptomatic profile. The position is taken that, while there are characteristic temporal features associated with the d isorder, the chronobiological system is essentially intact, although q uantitatively altered. It appears that the fundamental physiopathogene sis involves state boundary control mechanisms, which operate in state transitions. rather than chronobiological mechanisms affecting the ti ming of the manifestation of symptoms associated with the disease. We review our recent results from sleep-wake schedule studies designed to improve the maintenance of alertness in narcolepsy-cataplexy and repo rt new analyses of subjective sleepiness data. The schedules employed were designed to take preexisting circadian, circasemidian and ultradi an sleep-wake patterns of these patients into consideration.