Flipping the 'Sleep Switch' activates process 'O' (Onset/Offset) to produce alerting benefits of brief naps as well as more sustained sleep after nocturnal awakenings

Objectives:Brief naps (“power naps”), despite containing only lightsleep and producing little or no reduction of homeostatic sleep drive(Process S), nevertheless show significant recuperative effects.Therefore, Process S cannot account for the beneficial effects of briefnaps. Process O (onset/offset) was proposed to account for this briefnap benefit by rapidly dissipating inhibition to wakefulness after the ́switch ́to sleep. It operates in a similar manner to Process S but witha much shorter time constant. It is hypothesized here that Process Oshould also have a symmetrical effect when a brief awakening interrupts nocturnal sleep. It was hypothesized that longer episodesof sleep would follow brief awakenings in the last three hours of sleepthan would be predicted by Process S.