Sleep adaptations to seasonal changes in light and temperature

睡眠对光照和温度季节变化的适应

• 批准号: 1911857
• 负责人: Gandhi Yetish
• 金额: $ 14.8万
• 依托单位: Yetish Gandhi
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-15 至 2022-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1911857&HistoricalAwards=false
• 关键词: Sleep; adaptations; seasonal; changes; light

This award was provided as part of NSF's Social, Behavioral and Economic Sciences (SBE) Postdoctoral Research Fellowships (SPRF) program and SBE's Biological Anthropology program. The goal of the SPRF program is to prepare promising, early career doctoral-level scientists for scientific careers in academia, industry or private sector, and government. SPRF awards involve two years of training under the sponsorship of established scientists and encourage Postdoctoral Fellows to perform independent research. NSF seeks to promote the participation of scientists from all segments of the scientific community, including those from underrepresented groups, in its research programs and activities; the postdoctoral period is considered to be an important level of professional development in attaining this goal. Each Postdoctoral Fellow must address important scientific questions that advance their respective disciplinary fields. Under the sponsorship of Dr. Jerome Siegel at the University of California, Los Angeles, this postdoctoral fellowship award supports an early career scientist investigating sleep patterns in a modern hunter-gatherer population. Most people find it impossible to start their day without an alarm clock and a cup of coffee, but San hunter-gatherers do not have such amenities. During human evolution, early humans needed to figure out what time they needed to wake up each day and go to sleep each night in order to maximize their reproductive success in the context of a traditional hunter-gatherer lifestyle. The San population lives a similar lifestyle today, with most plant food being collected from wild sources, and all meat coming from hunting wild animals with bow-and-arrow. They live in a remote village where they do not have access to electricity or running water. People spend almost all of their time outside, including sleeping outside, except for when rain is expected.Earlier work in this and two other similar populations found that sleep duration is 5.7-7.1 hours per night, similar to the typical sleep duration observed in the United States. Sleep is normally initiated several hours after sunset and terminated at the coldest time of the 24-hour day. People sleep one hour longer per night in the winter months than they do in the summer months. These similarities in sleep patterns across three independent populations may be driven by biological adaptations to the natural environment. The follow-up research in this fellowship investigates how ambient conditions affect sleep within the San population. Changes in sleep timing and duration across the year, measured with wrist-worn accelerometers, can be analyzed in tandem with weather data to assess the relative influence of light and temperature on sleep. In addition, using portable EEG monitors, the distribution of REM and non-REM across the night can be assessed and compared between the summer and winter months, when sleep duration differs by about one hour per night. This research will identify the importance of temperature as a predictor of human sleep conditions, and begin to explain why sleep varies across the year in hunter-gatherer populations. These insights are important to better identify how our evolved sleep biology clashes with modern Western conditions, and how that clash may increase the risk of various sleep pathologies. They are also important first steps towards better understanding some of the adaptive challenges that faced early human ancestors as they transitioned from sleeping in trees in tropical climates, like chimpanzees, to the patterns of sleep conditions seen today.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项是美国国家科学基金会社会、行为和经济科学博士后研究奖学金（SPRF）项目和SBE生物人类学项目的一部分。SPRF计划的目标是为学术界、工业界或私营部门和政府的科学事业准备有前途的早期职业博士级科学家。SPRF奖励包括在知名科学家的赞助下进行为期两年的培训，并鼓励博士后进行独立研究。美国国家科学基金会寻求促进科学界各阶层的科学家，包括那些未被充分代表的群体的科学家，参与其研究项目和活动；博士后阶段被认为是实现这一目标的一个重要的专业发展阶段。每个博士后必须解决各自学科领域的重要科学问题。在加州大学洛杉矶分校杰罗姆·西格尔博士的赞助下，这项博士后奖学金支持一位研究现代狩猎采集人群睡眠模式的早期职业科学家。大多数人发现，没有闹钟和一杯咖啡就无法开始新的一天，但狩猎采集者没有这些便利设施。在人类进化过程中，早期人类需要弄清楚他们每天什么时候起床，什么时候睡觉，以便在传统的狩猎采集生活方式中最大限度地提高他们的繁殖成功率。今天的桑族人仍过着类似的生活方式，大部分植物性食物都是从野外采集的，所有的肉都来自于用弓箭狩猎野生动物。他们住在一个偏远的村庄，那里没有电，也没有自来水。人们几乎所有的时间都在户外度过，包括在户外睡觉，除非预计会下雨。早期对这一人群和另外两个类似人群的研究发现，睡眠时间为每晚5.7-7.1小时，与美国观察到的典型睡眠时间相似。睡眠通常在太阳落山几小时后开始，并在一天24小时中最冷的时候结束。人们在冬季比在夏季每晚多睡一个小时。在三个独立的人群中，睡眠模式的这些相似性可能是由对自然环境的生物适应所驱动的。这项研究的后续研究调查了环境条件如何影响桑族人的睡眠。一年中睡眠时间和持续时间的变化可以通过佩戴在手腕上的加速计来测量，并结合天气数据进行分析，以评估光线和温度对睡眠的相对影响。此外，使用便携式脑电图监测仪，可以评估和比较夏季和冬季夜间快速眼动和非快速眼动的分布，当睡眠时间每晚相差约一小时时。这项研究将确定温度作为人类睡眠状况预测指标的重要性，并开始解释为什么狩猎采集者的睡眠在一年中会有所不同。这些见解对于更好地确定我们进化的睡眠生物学是如何与现代西方条件相冲突的，以及这种冲突是如何增加各种睡眠病理的风险的，都很重要。这也是更好地理解早期人类祖先从像黑猩猩一样在热带气候的树上睡觉过渡到今天的睡眠模式时所面临的一些适应性挑战的重要的第一步。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。