During the COVID-19 pandemic, schools around the world rapidly transitioned from in-person to remote learning, providing an opportunity to examine the impact of in-person vs remote learning on sleep, circadian timing, and mood. We assessed sleep-wake timing using wrist actigraphy and sleep diaries over 1-2 weeks during in-person learning (n = 28) and remote learning (n = 58, where n = 27 were repeat assessments) in adolescents (age M ± SD = 12.79 ± 0.42 years). Circadian timing was measured under a single condition in each individual using salivary melatonin (Dim Light Melatonin Onset; DLMO). Online surveys assessed mood (PROMIS Pediatric Anxiety and Depressive Symptoms) and sleepiness (Epworth Sleepiness Scale – Child and Adolescent) in each condition. During remote (vs in-person) learning: (i) on school days, students went to sleep 26 minutes later and woke 49 minutes later, resulting in 22 minutes longer sleep duration (all P < .0001); (ii) DLMO time did not differ significantly between conditions, although participants woke at a later circadian phase (43 minutes, P = .03) during remote learning; and (iii) participants reported significantly lower sleepiness (P = .048) and lower anxiety symptoms (P = .006). Depressive symptoms did not differ between conditions. Changes in mood symptoms were not mediated by sleep. Although remote learning continued to have fixed school start times, removing morning commutes likely enabled adolescents to sleep longer, wake later, and to wake at a later circadian phase. These results indicate that remote learning, or later school start times, may extend sleep and improve some subjective symptoms in adolescents.

中文翻译：

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COVID-19 大流行期间的面对面教育与家庭教育：青春期早期睡眠、昼夜节律时间和情绪的差异

在 COVID-19 大流行期间，世界各地的学校迅速从面对面学习过渡到远程学习，这提供了一个机会来检查面对面学习与远程学习对睡眠、昼夜节律和情绪的影响。我们在青少年（年龄 M ± SD = 12.79 ± 0.42 年）。使用唾液褪黑激素（Dim Light Melatonin Onset；DLMO）在单个条件下测量每个个体的昼夜节律时间。在线调查评估了每种情况下的情绪（PROMIS 小儿焦虑和抑郁症状）和嗜睡（Epworth 嗜睡量表 - 儿童和青少年）。在远程（与面对面）学习期间：(i) 在上学日，P  < .0001); (ii) DLMO 时间在不同条件下没有显着差异，尽管参与者在远程学习期间在较晚的昼夜节律阶段醒来（43 分钟，P  = .03）；(iii) 参与者报告显着降低嗜睡 ( P  = .048) 和降低焦虑症状 ( P  = .006)。抑郁症状在不同情况下没有差异。情绪症状的变化不是由睡眠介导的。尽管远程学习仍然有固定的上学时间，但取消早上的通勤时间可能会使青少年睡得更久、醒得更晚，并在更晚的昼夜节律阶段醒来。这些结果表明，远程学习或延迟上学时间可能会延长青少年的睡眠时间并改善一些主观症状。