Szymczak J T
J Comp Physiol A. 1987 Aug;161(2):321-7. doi: 10.1007/BF00615252.
Sleep and wake states were monitored polygraphically in the rook Corvus frugilegus, under the natural photoperiod and temperature. The indices of sleep and wake states in the rook were similar to those described previously for birds in general. The appearance of sleep episodes was confined to the dark part of the photoperiod. Slow wave sleep (SWS) showed a tendency to increase during the course of the night, while paradoxical sleep (PS) showed the opposite trend. The distribution of short SWS episodes were clustered into two groups, one group occurred in the period following the onset of sleep and the other, less prominent group occurred towards the end of sleep. The longest episodes of SWS appeared in the second half of the night, whereas those of PS appeared after onset of sleep.
在自然光照周期和温度条件下，通过多导睡眠图对小嘴乌鸦（Corvus frugilegus）的睡眠和觉醒状态进行了监测。小嘴乌鸦的睡眠和觉醒状态指标与之前一般鸟类所描述的相似。睡眠阶段出现在光照周期的黑暗部分。慢波睡眠（SWS）在夜间过程中有增加的趋势，而快速眼动睡眠（PS）则呈现相反的趋势。短时间慢波睡眠阶段的分布聚为两组，一组出现在睡眠开始后的时间段，另一组不太明显的组出现在睡眠接近结束时。最长的慢波睡眠阶段出现在夜间后半段，而快速眼动睡眠阶段则出现在睡眠开始后。
