Effects of experimentally-induced sleep fragmentation on sleep and sleepiness.

Abstract

ABSTRACTThe effects of two levels of sleep fragmentation on sleep and daytime sleepiness were investigated in young adult males. Experimental subjects were informed while awake that tones would be presented periodically throughout the night and that their task was to terminate the tone by taking a deep breath. Eight subjects received tones after each minute of sleep and 8 received tones after each 4 min of sleep. Control subjects (N=8) HI did not receive (ones. The subjects were tested for daytime sleepiness using the Multiple Steep latency Test. It was found that: 1) subjects responded reliably lo tones presented during sleep; 2) behavioral control was accompanied by brief electro‐physiological indices of arousal on almost all trials, and occasionally led to fall awakenings; 3) sleep was markedly altered in the 1‐min condition; 4) a relatively small effect on sleep (reduced stage 4 sleep) was produced by the 4‐min condition, and 5) daytime sleepiness was increased by the 1‐min condition but not the 4‐min condition. It was concluded that the most parsimonious explanation of these results is (he Continuity of Sleep hypothesis.