EEG Signatures of Offline Memory Reactivation and Consolidation

描述(由申请人提供)：休息和睡眠状态对最佳人类认知功能至关重要。即使在睡眠期间，当感觉输入和意识最少时，大脑也会继续处理前一天的信息。在动物身上的研究表明，在清醒时对环境的探索中首次看到的神经活动模式，后来在安静的休息和睡眠中被重新激活。在人类中，睡眠巩固并增强了先前形成的记忆。伴随着这种依赖睡眠的记忆处理，对最近经历的记忆有助于形成我们通常所说的“梦”的图像、思想和叙述。被认为是长期记忆形成的关键组成部分，人类学习后记忆的重新激活还没有得到充分的研究，而且仍然知之甚少。这里提出的研究将提供第一个基于脑电的人类脱机记忆重新激活的特征，分析在虚拟导航任务编码期间以及训练后休息和睡眠期间记录的脑电信号的全局空间模式。同时，对正在进行的主观体验的采样提供了一种在认知水平上重新激活记忆的措施。利用“微状态分析”技术，我们的初步发现表明，在随后的睡眠中，与学习相关的脑电模式再次出现，这种“重新激活”的程度预示着睡眠后任务的改善。如果成功，这项拟议的研究将证实，离线重新激活是人类记忆巩固的基础，这一点在电生理和认知测量中都有表达。这个项目的重点是描述多层次分析中的记忆巩固(整合行为、电生理学和意识体验的测量)，这与NIMH新的研究领域标准倡议(RDoC)中提出的“睡眠/觉醒结构”非常一致。

DESCRIPTION (provided by applicant): States of rest and sleep are critical for optimal human cognitive function. Even during sleep, when sensory input and conscious awareness are minimal, the brain continues to process information from the previous day. Research in animals demonstrates that patterns of neural activity first seen during waking exploration of an environment are later "reactivated" during quiet rest and sleep. In humans, sleep consolidates and enhances previously formed memories. In parallel with this sleep-dependent memory processing, memories of recent experiences contribute to the images, thoughts, and narratives that we commonly call "dreams". Thought to be a critical component of long-term memory formation, post-learning reactivation of memories in humans has not been adequately studied, and is still poorly understood. The research proposed here would provide the first EEG-based characterization of offline memory reactivation in humans, analyzing global spatial patterns of the EEG signal recorded during encoding of a virtual navigation task, and during post-training rest and sleep. In parallel, the sampling of ongoing subjective experience provides a measure of memory reactivation at the cognitive level. Using the technique of "microstate analysis", our preliminary findings suggest that learning- related EEG patterns reappear during subsequent sleep, and that the extent of this "reactivation" predicts post- sleep task improvement. If successful, the proposed research would confirm that offline reactivation underlies memory consolidation in humans, as expressed in both electrophysiological and cognitive measures. In its focus on describing memory consolidation across multiple levels of analysis (integrating measures of behavior, electrophysiology, and conscious experience), this project is strongly in line with the proposed "sleep/wake construct" in NIMH's new Research Domain Criteria initiative (RDoC).