ABSTRACT

The interactions of the principal circadian clock with the homeostatic sleep process create the time-sensitive window for easy falling asleep in the evening, which is affected by a thermoregulatory process. It has been hypothesized that the changes in skin and core body temperatures before the sleep onset might play a direct role in sleep regulation. To determine this time window, we recorded from 20 healthy participants (11 women and 9 men), aged 26–58 years, one overnight own-home ambulatory polysomnography and measured continuously wrist skin temperature with a wrist-worn accelerometer containing a skin temperature thermometer. Wrist skin temperatures which were read out from the thermometer of the accelerometers were modeled using linear mixed models, and the linear effect of time before the sleep onset on wrist temperature was analyzed using a mixed model with the sex and age as the covariates. We found that wrist skin temperatures increased on average by 0.6° (of Celcius) in 10 min prior to the sleep onset and could be tracked robustly along a slope of time (p = 0.004). Our current findings may be useful in further characterizing the window of time and its boundaries for easy falling asleep.

摘要

主要生物钟与稳态睡眠过程的相互作用为晚上容易入睡创造了时间敏感窗口，这受体温调节过程的影响。据推测，入睡前皮肤和核心体温的变化可能在睡眠调节中起直接作用。为了确定这个时间窗口，我们记录了 20 名年龄在 26-58 岁的健康参与者（11 名女性和 9 名男性）的一夜自己在家的动态多导睡眠图，并使用包含皮肤温度温度计的腕戴式加速度计连续测量腕部皮肤温度. 使用线性混合模型对从加速度计的温度计读出的手腕皮肤温度进行建模，并使用性别和年龄作为协变量的混合模型分析了入睡前时间对手腕温度的线性影响。我们发现，在入睡前 10 分钟，手腕皮肤温度平均增加了 0.6°（摄氏度），并且可以沿着时间斜率稳健地跟踪（p = 0.004）。我们目前的研究结果可能有助于进一步描述时间窗口及其容易入睡的边界。