Effects of sleep of restricted sleep. A cat case study

One male cat was adapted to different schedules of restricted sleep. The cat was allowed to go to sleep during a certain number of hours per day. During the rest of the 24 h period, wakefulness was enforced by means of a treadmill. The following schedules of restricted sleep were run: 12 h sleep--12 h treadmill (12S--12T), 8S--16T, 4S--20T. The cat was also adapted to a 36 h day: 12S--24T. The sleep was investigated after at least 2 weeks on each schedule and compared to ad lib. sleep (24S--0T). As available sleep time bacame shorter, the composition of the sleep changed. LSWS (in % of available sleep time) decreased, while DSWS % and REM sleep % increased. The length of the DSWS and REM sleep episodes increased with decreasing sleep time, as did sleep cycle length.