Influence of sleep regularity on circadian rhythms, learning, performance, and mood

 描述（由申请人提供）：午夜不再是发达国家个人的午夜。许多青少年和年轻人在午夜醒来并活跃。人工照明、咖啡因和闹钟使睡眠/清醒+亮/暗时间表与外部环境分离。此外，许多人在工作/上学和非工作/非上学日有不同的时间表，在非工作/非上学日有更晚的就寝时间，更晚的醒来时间和更频繁的午睡。我们和其他人已经发现，不规律的睡眠/觉醒时间表与较晚的昼夜节律、较差的情绪、较差的学习成绩以及一些健康指标（如体重和精神疾病）之间存在相关性。然而，这些是相互关联的，而不是因果联系。确定可改变的行为（如可变的睡眠时间）影响生理的机制对于制定有效的教育或治疗策略至关重要。我们提出了一个实验来测试不规则和规则的睡眠/觉醒时间表对昼夜节律，睡眠，认知能力，情绪和学习的影响。我们将研究一个年轻的成年人群体，因为这是人类发展的一个时期，可变的睡眠时间表是普遍的，不规则的时间表对昼夜节律，睡眠倾向，表现，情绪和学习的后果可能是明显的。从拟议的工作的结果将使我们能够确定是否是不规则的 睡眠/清醒亮/暗（SW/LD）时间表，延迟昼夜节律，扰乱表现，情绪和学习。使用我们的睡眠规律性指数（SRI，睡眠规律性的定量测量），我们将在三周的门诊筛查期间根据个人的睡眠-觉醒模式识别和选择具有不规律和规律睡眠/觉醒时间表的个人。然后将每组的个体随机分配至不定期或定期SW/LD计划进行住院评估。在研究的住院部分，将对昼夜节律、睡眠倾向、认知表现（包括警觉性注意力、睡眠依赖性和长期学习）和情绪进行评估。我们的研究结果将有助于定义多个生理系统之间的生理联系，包括睡眠/觉醒，光敏感过程（例如，昼夜节律、警觉性、激素）、认知表现和情绪。减少预定的睡眠变异性没有药理学副作用，并可能具有额外的健康益处。设计有效的治疗策略，以减少变异性，需要了解的生理和环境因素，可能介导和加强不规则性。我们的研究结果将有助于阐明这些机制，并将适用于高中和大学生，以及成年人轮班或夜间工作或经历时差。研究结果可用于公共卫生论坛，包括 关于睡眠时间及其对昼夜节律、表现、学习、情绪和安全的影响的教育活动。

 DESCRIPTION (provided by applicant): Midnight is no longer mid-night for individuals in the developed world. Many adolescents and young adults are awake and active at midnight. Artificial lighting, caffeine, and alarms have enabled this dissociation of sleep/wake+light/dark schedules from the external environment. In addition, many individuals have different schedules on work/school and non-work/non-school days, with later bedtimes, later wake times, and more frequent naps on non-work/non-school days. We and others have found correlations between irregular sleep/wake schedules and later circadian timing, poorer mood, poorer academic performance, and some health metrics, such as weight and psychiatric disorders. These, however, are correlations and not causal links. Identifying mechanisms by which modifiable behaviors, such as variable sleep timing, impact physiology is vital to developing effective educational or treatment-based strategies. We propose an experiment to test the effects of irregular and regular sleep/wake schedules on circadian timing, sleep, cognitive performance, mood, and learning. We will study a young adult population, as this is a time in human development when variable sleep schedules are prevalent and the consequences of irregular schedules on circadian timing, sleep propensity, performance, mood, and learning may be pronounced. The results from the proposed work will allow us to determine if it is the irregularity of the sleep/wake light/dark (SW/LD) schedule that delays circadian timing and disrupts performance, mood, and learning. Using our Sleep Regularity Index (SRI, a quantitative measure of sleep regularity), we will identify and select individuals with Irregular and Regular sleep/wake schedules based on the individual's sleep-wake pattern during three weeks of outpatient screening at home. Individuals from each group will then be randomly assigned to either an Irregular or Regular SW/LD schedule for an inpatient assessment. Assessments of circadian phase, sleep propensity, cognitive performance including vigilant attention, sleep-dependent and long-term learning, and mood will be conducted during the inpatient portion of the study. Our findings will help define physiological links among multiple physiological systems, including sleep/wake, light-sensitive processes (e.g., circadian rhythms, alertness, hormones), cognitive performance, and mood. Reducing scheduled sleep variability has no pharmacologic side-effects and may have additional health benefits. Designing effective therapeutic strategies for reducing variability requires an understanding of the physiological and environmental factors that may mediate and reinforce irregularity. Our results will help to elucidate these mechanisms and will be applicable to high school and college students, as well as adults working shift or night work or experiencing jet-lag. The findings may be utilized in public health forums, including educational campaigns about sleep timing and its effects on circadian rhythms, performance, learning, mood, and safety.