Methods: the absence of the righting reflex was considered as the sleep onset and the duration of the loss of the righting reflex was recorded as the sleeping time.

方法：以翻正反射消失为睡眠开始的指标，至翻正反射恢复作为睡眠时间。

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In a follow-up study with the virtual-skiing game Alpine Racer, 14 of 16 students reported seeing skiing images at sleep onset (as did three people who were merely observing the experiment.)

在一项用虚拟滑雪游戏《高山滑雪》(Alpine Racer)进行的后续研究中，16名学生中的14名报告说，他们在刚开始入睡时见到了滑雪的图像(3位只是观察了这个实验的人也是如此)。

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Results Overlap syndrome had increased number of WASO (wake after sleep onset), fallen asleep the incubation period shorten, sleep apnea time was long, and the nocturnal hypoxemia was obvious.

结果重叠综合征患者觉醒次数增加，入睡潜伏期缩短，睡眠呼吸暂停时间长，夜间低氧血症明显。

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Production of the chemical at night stimulates the onset of sleep.

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This is a condition that causes the sudden onset of sleep paralysis the loss of muscle tone that occurs when we sleep during waking hours, often as a result of strong emotions.

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The sleep test also was normal, except for a delayed onset of rapid-eye-movement sleep, with unknown medical significance.

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