A multimodal study of delay activity contributions to short and long term memory

项目总结/摘要 延迟活动是在相关刺激的编码和相关刺激的产生之间的几秒钟内发生的神经活动。 记忆提取延迟活动是工作记忆的关键组成部分，工作记忆是一种认知过程，使我们能够 在线保存信息并操纵它以实现当前和未来的目标。虽然延迟活动已经 使用各种神经科学记录方法和不同的方法在动物和人类中进行了广泛的研究。 尽管数据分析水平很高，但在理解延迟活动的机制方面仍存在一些差距 有助于短期和长期记忆。最近的研究质疑长期存在的理论 该框架认为，提高和持续的延迟活动是记忆维持的基础。这些调查结果 研究表明，延迟活动往往是短暂的或突发性的，无人看管的刺激甚至可能是 保持在活动静默隐藏状态。这些新发现促使这里概述的实验， 了解可观察到的延迟活动如何有助于记忆的形成。这项建议将联合收割机 时间分辨率脑电图和高空间分辨率功能MRI方法在人类中测试 参与者的首要假设，即延迟活动的早期和晚期成分有助于记忆 阵第一个目标是研究不同的延迟间隔时间和内容对延迟时间的影响 使用脑电图（EEG）和功能性磁共振技术， 成像（fMRI）。假设EEG延迟时间与EEG延迟时间之间存在时间对应关系， 同步和BOLD-fMRI振幅，两者与随后的记忆呈正相关。的 第二个目的是研究延迟期脑电同步化/去同步化和大脑皮层-皮层fMRI连接对记忆的影响。假设早期同步化和后期去同步化 在延迟期反映了大脑皮层结合和皮质-皮质再激活之前的记忆 检索第三个目标将研究EEG延迟活动和随后的睡眠纺锤波对记忆的影响。 该假说认为，更多的延迟活动将在学习后睡眠期间引起长期记忆巩固过程。这三个目标的完成将有助于对以下问题的基本理解： 延迟活动在记忆中的作用。这些结果将提供有价值的见解，为什么某些心理健康 和神经系统疾病，包括异常的延迟活动，导致复杂的模式， 长期记忆障碍

PROJECT SUMMARY/ABSTRACT Delay activity is neural activity that occurs within a few seconds between the encoding of relevant stimuli and memory retrieval. Delay activity is a key component of working memory, a cognitive process that allows us to hold information online and manipulate it to realize immediate and future goals. While delay activity has been extensively studied in animals and humans using a variety of neuroscientific recording methods and different levels of data analysis, there remain several gaps in understanding the mechanisms by which delay activity contributes to both short- and long-term memory. Recent studies question the long-standing theoretical framework that elevated and sustained delay activity is the basis for memory maintenance. Findings from these studies suggest that delay activity is often transient or burst-like, and that unattended stimuli may even be maintained in activity-silent hidden states. These new findings motivate the experiments outlined here to understand how observable delay activity contributes to memory formation. This proposal will combine high temporal resolution electroencephalographic and high spatial resolution functional MRI methods to test in human participants the overarching hypothesis that early and late components of delay activity contribute to memory formation. The first aim will study the effects of varying the delay interval duration and content on delay period activity and memory using the techniques of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI). The hypothesis is there will be a temporal correspondence between EEG delay period synchronization and BOLD-fMRI amplitude, with a positive relationship of both to subsequent memory. The second aim will study the effects of delay period EEG synchronization/desynchronization and hippocampal-cortical fMRI connectivity on memory. The hypothesis is that early synchronization and later desynchronization in delay periods reflects hippocampal-cortical binding and cortico-cortical reactivation preceding memory retrieval. The third aim will study the effects of EEG delay activity and subsequent sleep spindles on memory. The hypothesis is that more delay activity will elicit long-term memory consolidation processes during a post-learning sleep period. Together the completion of these three aims will contribute to a basic understanding of the role of delay activity in memory. The outcomes will provide valuable insight into why certain mental health and neurological disorders, which include aberrant delay activity, lead to complex patterns of both short- and long-term memory impairments.