Barbato G, Barker C, Bender C, Giesen H A, Wehr T A
Clinica Psichiatrica, II Facoltà di Medicina, Università di Napoli, Italy.
Electroencephalogr Clin Neurophysiol. 1994 Apr;90(4):291-7. doi: 10.1016/0013-4694(94)90147-3.
The sleep patterns of 8 normal subjects living in a winter-type photoperiod (10 h light and 14 h darkness; LD 10:14) for 4 weeks were characterized by the presence of periods of spontaneous wakefulness alternating with periods of spontaneous sleep. Transitions from sleep to wakefulness occurred much more frequently out of REM sleep than out of NREM sleep (P < 0.002). REM periods that terminated in wakefulness showed shorter REM durations (P < 0.0005) and higher REM densities (P < 0.0005) than REM periods that did not terminate in wakefulness. The authors discuss these results in terms of a possible relationship between REM density and arousal level. The higher REM density preceding wakefulness and the increased number of REM periods terminating in spontaneous awakenings could reflect an enhanced level of a brain arousing process, resulting from reduced sleep pressure in the extended nights.
8名正常受试者在冬季光照周期（10小时光照和14小时黑暗；LD 10:14）下生活4周后的睡眠模式，其特点是自发觉醒期与自发睡眠期交替出现。从睡眠到觉醒的转换在快速眼动睡眠（REM睡眠）中比在非快速眼动睡眠（NREM睡眠）中更为频繁（P < 0.002）。以觉醒结束的REM期与未以觉醒结束的REM期相比，显示出更短的REM持续时间（P < 0.0005）和更高的REM密度（P < 0.0005）。作者根据REM密度与唤醒水平之间可能的关系讨论了这些结果。觉醒前较高的REM密度以及以自发觉醒结束的REM期数量增加，可能反映了大脑唤醒过程水平的提高，这是由于长夜中睡眠压力降低所致。
