Gillberg M, Akerstedt T
National Defence Research Establishment, Department 5, Stockholm, Sweden.
Sleep. 1991 Apr;14(2):147-54.
Eight subjects participated in an experiment in which sleep stages and electroencephalographic (EEG) power density during the first sleep cycles (and where such appeared, also second cycles) were studied in a design involving 8, 4, 2 or 0 hr of progressively postponed night-time sleep. Each of these four manipulations was followed by a day-time sleep beginning at 1100 hr. No significant changes in the duration of the first sleep cycle appeared. As the prior sleep loss increased both SWE (slow-wave energy; accumulated EEG delta power density) and SWA (slow-wave activity; EEG delta power per minute) increased during the 1100-hr sleeps. This was observed for the entire cycles, the nonrapid eye movement (NREM) periods, and the SWS periods, respectively. SWS latency decreased and SWS duration increased, respectively, markedly with prior waking. Also, for the progressively postponed sleeps (started at 2300 hr, 0300 hr, 0500 hr and 1100 hr) there were changes, but not as clear. After 28 hr of continuous waking there was a marked increase of SWA during SWS. Also, at this level there was a spill over of SWA to the second cycle. It is suggested that there might be a limit to the amount and intensity of SWS that can be accommodated in the first sleep cycle and that this limit is reached before the appearance of REM sleep.
八名受试者参与了一项实验，该实验采用一种设计，研究了在最初睡眠周期（若有第二个睡眠周期也包括在内）中的睡眠阶段和脑电图（EEG）功率密度，该设计涉及将夜间睡眠逐渐推迟8、4、2或0小时。这四种操作中的每一种之后都紧接着一次从11:00开始的日间睡眠。第一个睡眠周期的时长未出现显著变化。随着先前睡眠剥夺的增加，在11:00的睡眠期间，慢波能量（SWE；累积的EEGδ功率密度）和慢波活动（SWA；每分钟EEGδ功率）均增加。分别在整个周期、非快速眼动（NREM）期和慢波睡眠（SWS）期观察到了这种情况。SWS潜伏期随着先前清醒时间的增加而显著缩短，而SWS时长则显著增加。此外，对于逐渐推迟的睡眠（分别在23:00、03:00、05:00和11:00开始）也有变化，但不太明显。在连续清醒28小时后，SWS期间的SWA显著增加。而且，在这个水平上，SWA还会延续到第二个睡眠周期。研究表明，第一个睡眠周期能够容纳的SWS的量和强度可能存在一个限度，并且在快速眼动睡眠出现之前就达到了这个限度。
