Stress at learning interacts with sleep to optimally consolidate emotional memories

学习压力与睡眠相互作用，以最佳方式巩固情感记忆

• 批准号: 1539361
• 负责人: Elizabeth Kensinger
• 金额: $ 55.1万
• 依托单位: Boston College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-15 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1539361&HistoricalAwards=false
• 关键词: Stress; learning; interacts; sleep; optimally

We spend nearly a third of our lives sleeping, yet research is just beginning to shed light on the multitude of benefits that are conveyed by sleep. One important benefit of sleep is to strengthen the memories we form during the day, particularly if those memories have some future utility. But how is future utility determined? This research tests a new model which proposes that sleep selectively strengthens memories for events that are associated with elevated levels of stress hormones or with elevated physiological arousal, such as changes in heart rate or sweating, when we first encounter them. This research is significant for a number of reasons. In a society in which many people are chronically sleep deprived, and report high levels of stress, it is important to understand how interactions between stress and sleep may influence the ability for the human brain to store and remember information. This research will clarify how stressful situations are remembered over time, which may yield new insights into why sleep disruption often co-occurs with affective disorders (such as depression) and memory problems. The project provides training in the integrated use of functional magnetic resonance imaging (fMRI), stress, and sleep scoring and recording methods; it continues a summer research exchange program between Boston College and Notre Dame; and it supports high school internships, exposing diverse students to neuroscience, a field that is not included in most high school curricula. The project also contains an outreach component that strives to inform community members of the importance of prioritizing sleep and the value of stress management.Emotional memories form the core of our personal histories, marking our greatest achievements and worst defeats. While our ability to remember and learn from these events is critical for survival, how we remember them can also influence the development of affective disorders, such as clinical depression and post-traumatic stress disorder (PTSD). Negative experiences enjoy a privileged status in memory, being better remembered than most neutral events, yet there is a limited understanding of how such memories are consolidated and stored. The PIs' prior research demonstrated that sleep selectively preserves emotional memories, but only if participants had higher resting cortisol levels and elevated psychophysiological responses at the time of encoding. We now propose to directly manipulate encoding levels of stress and to examine how stress at encoding may enhance connectivity within emotional-memory neural networks (Aim 1); how sleep may preserve this enhanced connectivity over time (Aim 2); and how these effects of stress and sleep may combine to enhance emotional memory performance (Aim 3) and neural cohesiveness in emotional memory networks during memory retrieval (Aim 4). It is widely thought that stress disrupts sleep, and sleep affects sensitivity to stress, yet there are few empirical tests of their shared influence on cognition and emotion. However, these interactions are critical to understand given the 1) increase in stress-related illnesses and sleep disruption and the concurrent rise in affective disorders, 2) prevalence of PTSD in the military, and 3) likely impact of stress and sleep disruption in the classroom and workplace. By uniting the traditionally separate fields of sleep and stress, and examining the interactive effects of processes that unfold during encoding and consolidation, this novel research is expected to yield transformative findings. The proposal strengthens a productive collaboration between Elizabeth Kensinger at Boston College (BC), with expertise in affective neuroscience and Jessica Payne at Notre Dame (ND), with expertise in sleep and stress effects on memory.

我们一生中将近三分之一的时间都在睡觉，然而研究才刚刚开始揭示睡眠带来的诸多好处。睡眠的一个重要好处是加强我们在白天形成的记忆，特别是如果这些记忆在未来有一些用处。但是未来的效用是如何确定的呢？这项研究测试了一个新模型，该模型提出，当我们第一次遇到与应激激素水平升高或与生理唤醒（如心率或出汗的变化）升高有关的事件时，睡眠会选择性地加强对这些事件的记忆。这项研究意义重大，原因有很多。在一个许多人长期睡眠不足，并报告高水平压力的社会中，了解压力和睡眠之间的相互作用如何影响人类大脑存储和记忆信息的能力是很重要的。这项研究将阐明压力情况是如何随着时间的推移而被记住的，这可能会对为什么睡眠中断经常与情感障碍（如抑郁症）和记忆问题同时发生产生新的见解。该项目提供综合使用功能性磁共振成像（fMRI）、压力和睡眠评分和记录方法的培训；它继续在波士顿学院和圣母大学之间开展夏季研究交流项目；它还支持高中实习，让不同的学生接触到大多数高中课程中不包括的神经科学领域。该项目还包含一个外联部分，努力告知社区成员优先考虑睡眠的重要性和压力管理的价值。情感记忆构成了我们个人历史的核心，标志着我们最伟大的成就和最糟糕的失败。虽然我们从这些事件中记忆和学习的能力对生存至关重要，但我们如何记住它们也会影响情感障碍的发展，如临床抑郁症和创伤后应激障碍（PTSD）。负面经历在记忆中享有特权地位，比大多数中性事件更容易被记住，但人们对这些记忆如何巩固和储存的理解有限。pi先前的研究表明，睡眠选择性地保留了情绪记忆，但前提是参与者在编码时具有更高的静息皮质醇水平和更高的心理生理反应。我们现在建议直接操纵压力的编码水平，并研究编码时的压力如何增强情绪记忆神经网络内的连通性（目的1）；睡眠如何随着时间的推移保持这种增强的连通性（目标2）；以及压力和睡眠的这些影响如何结合起来增强情绪记忆表现（目的3）和记忆提取过程中情绪记忆网络的神经凝聚力（目的4）。人们普遍认为，压力会扰乱睡眠，而睡眠会影响对压力的敏感性，但很少有关于它们对认知和情绪的共同影响的实证测试。然而，考虑到1)压力相关疾病和睡眠中断的增加以及情感障碍的同时增加，2)军队中创伤后应激障碍的流行，以及3)课堂和工作场所压力和睡眠中断的可能影响，这些相互作用对于理解至关重要。通过将传统上分离的睡眠和压力领域结合起来，并检查在编码和巩固过程中展开的过程的相互作用，这项新颖的研究有望产生变革性的发现。该提案加强了波士顿学院（BC）的伊丽莎白·肯辛格（Elizabeth Kensinger）在情感神经科学方面的专业知识和圣母大学（Notre Dame）的杰西卡·佩恩（Jessica Payne）在睡眠和压力对记忆的影响方面的专业知识之间的富有成效的合作。