NCS-FO: Collaborative Research: Sleep's role in determining the fate of individual memories

NCS-FO：合作研究：睡眠在决定个体记忆命运中的作用

• 批准号: 1533511
• 负责人: Kenneth Norman
• 金额: $ 59.41万
• 依托单位: Princeton University
• 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: 2015-09-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1533511&HistoricalAwards=false
• 关键词: NCS; FO; Collaborative; Research; Sleep

Identifying the cognitive, computational and neural mechanisms responsible for determining why some memories survive when others fade is one of the many grand challenges facing researchers of the human mind and brain. It is widely understood that sleep plays a critical role in long-term remembering, yet what exactly happens during sleep to affect the persistence of memories remains largely unknown. This project brings together a team of researchers who will integrate multiple independent lines of work in cognitive neuroscience, cognitive psychology, and computer science in order to investigate the precise mechanisms undergone by recently-formed memory representations as a person sleeps and how these mechanisms determine which memories survive and which fade. The proposed integration of cutting-edge neural data analysis methods for EEG and neuroimaging data, basic human memory theory, and neural network modeling make possible the ability to non-invasively track individual memories in the human brain as they compete with each other and are modified during sleep. The potential advances from this work could impact education, training situations, and public health by facilitating the development of new strategies for ensuring that important memories survive after initial learning.Research suggests that memories compete for neural space such that reactivating one particular memory can exert "collateral damage" on other related memories. In other words, accessing one memory can come at the expense of later being able to access other nearby memories in the network space. The proposed studies test the hypothesis that importance shapes neural dynamics during sleep by selectively boosting memory reactivation; this boost ensures that important memories out-compete related memories during sleep, resulting in strengthening of important memories and weakening of less-important memories. To test this hypothesis, competition between memories will be elicited during sleep by playing sound cues, each of which was linked (during wake) to two different picture-location memories. Multiple interlocking approaches will track how memory competition during sleep shapes a memory's persistence versus fading. Neural network models will be used to generate predictions about how reward responses during encoding shape competitive dynamics during sleep, and how these competitive dynamics determine the eventual fates of competing memories. Predictions will be tested by using fMRI to measure neural activity associated with reward processing during encoding, EEG to measure brain activity during sleep, and pattern classifiers to decode memory activation from the sleep EEG data. Observations of competitive dynamics during sleep will then be related to later memory performance and to multivariate fMRI measures of memory change. The project has the potential to provide, for the first time, a comprehensive look "under the hood" at the life of a memory as it is acquired, processed during sleep, and eventually recalled. Pivotal knowledge will be gained about how variance in reward processing at encoding influences sleep replay dynamics, and about how sleep replay dynamics affect subsequent memory performance and the structure of neural representations.

识别认知、计算和神经机制，这些机制决定了为什么一些记忆在另一些记忆消失时仍然存在，这是人类思维和大脑研究人员面临的众多重大挑战之一。众所周知，睡眠在长期记忆中起着至关重要的作用，然而，睡眠中究竟发生了什么影响记忆的持久性，在很大程度上仍然未知。该项目汇集了一组研究人员，他们将整合认知神经科学、认知心理学和计算机科学等多个独立领域的工作，以研究人在睡眠时新近形成的记忆表征所经历的精确机制，以及这些机制如何决定哪些记忆能够存活，哪些记忆会消失。将脑电图和神经成像数据的尖端神经数据分析方法、基本人类记忆理论和神经网络建模相结合，使非侵入性地跟踪人类大脑中相互竞争并在睡眠中被修改的个体记忆成为可能。这项工作的潜在进展可以通过促进新策略的发展来确保重要记忆在初次学习后仍然存在，从而影响教育、培训情况和公共卫生。研究表明，记忆会争夺神经空间，因此重新激活一段特定的记忆会对其他相关记忆造成“附带损害”。换句话说，访问一个内存的代价是以后无法访问网络空间中邻近的其他内存。拟议的研究验证了这样一个假设：重要性通过选择性地促进记忆再激活来塑造睡眠期间的神经动力学；这种促进确保了重要的记忆在睡眠中胜过相关的记忆，从而加强了重要的记忆，削弱了不太重要的记忆。为了验证这一假设，在睡眠期间，通过播放声音提示来引发记忆之间的竞争，每个声音提示（在清醒时）都与两个不同的图片位置记忆相关联。多种联锁方法将追踪睡眠期间的记忆竞争如何塑造记忆的持久性和消退。神经网络模型将用于预测编码过程中的奖励反应如何形成睡眠中的竞争动态，以及这些竞争动态如何决定竞争记忆的最终命运。预测将通过功能磁共振成像（fMRI）来测试编码过程中与奖励处理相关的神经活动，脑电图（EEG）来测试睡眠期间的大脑活动，模式分类器（pattern classifier）来解码睡眠脑电图数据中的记忆激活。在睡眠过程中观察到的竞争动态将与后来的记忆表现和记忆变化的多变量fMRI测量相关联。该项目有可能第一次全面了解记忆的“底层”，因为它是在睡眠中获得、处理和最终被回忆起来的。将获得关于编码时奖励处理的差异如何影响睡眠重放动态，以及睡眠重放动态如何影响随后的记忆表现和神经表征结构的关键知识。