Borbély A A
Brain Res. 1976 Sep 17;114(2):305-17. doi: 10.1016/0006-8993(76)90673-9.
The vigilance states and motor activity of the rat were recorded during ultrashort light-dark (LD) cycles. The LD schedules were the following: 10 min light -- 10 min dark (LD 10:10), LD 7.5:7.5, LD 5:5 and LD 2.5:2.5. With all short LD schedules, paradoxical sleep (PS) and high motor activity occurred more frequently during dark periods than during light. PS and motor activity were rapidly enhanced by darkness and inhibited by light, whereas the percentages of total sleep and slow wave sleep were only gradually decreased during the dark periods and increased during light. Compared to the LD 12h:12h control days, sleep was enhanced by all short LD schedules, an effect that was most marked in the circadian phase of maximum waking (corresponding to the LD 12h:12h dark period). The short LD cycles interacted with an intrinsic sleep cycle, whose period is approximately 10 min. Interval histograms of PS episodes showed that an optimal synchronization of the ultradian sleep rhythm is achieved when the period of the LD cycle or its multiple correspond also to 10 min. It is suggested that the response of PS and motor activity to changes in illumination may be due to common mechanisms.
在超短明暗（LD）循环期间记录大鼠的警觉状态和运动活动。LD时间表如下：10分钟光照-10分钟黑暗（LD 10:10）、LD 7.5:7.5、LD 5:5和LD 2.5:2.5。在所有短LD时间表中，异相睡眠（PS）和高运动活动在黑暗期比在光照期更频繁地出现。PS和运动活动在黑暗中迅速增强，在光照下受到抑制，而总睡眠时间和慢波睡眠时间的百分比在黑暗期仅逐渐下降，在光照期增加。与LD 12小时:12小时的对照日相比，所有短LD时间表都增强了睡眠，这种效果在最大清醒的昼夜节律阶段（对应于LD 12小时:12小时的黑暗期）最为明显。短LD循环与一个内在睡眠周期相互作用，其周期约为10分钟。PS发作的间隔直方图显示，当LD循环的周期或其倍数也对应于10分钟时，超日睡眠节律可实现最佳同步。有人提出，PS和运动活动对光照变化的反应可能归因于共同的机制。
