State Dependent Aspects of Cognition

描述（由申请人提供）：在过去的十年中，我们对睡眠依赖性记忆巩固的理解急剧增加，将其从一个普遍不可信（或最多被忽视）的概念转变为记忆和睡眠研究人员普遍接受的原则，甚至在本科心理学教科书中也可以找到。这项工作建立了睡眠和记忆功能之间的紧密联系。但鉴于睡眠和记忆的复杂性，每一个都包括多个阶段和亚型，即使是这种现象的最基本特征也仍然不清楚。哪些类型的记忆在睡眠中得到巩固？睡眠期间哪些成分会发生巩固？哪些睡眠阶段介导了这种巩固？睡眠依赖性巩固的生理过程是什么？迄今为止，大多数研究都试图将特定类别的记忆巩固分配给离散的睡眠阶段，例如将程序性记忆巩固到REM睡眠或将陈述性记忆巩固到慢波睡眠（SWS）。但是，这种简单的二分法的例外情况几乎超过了支持研究的数量。几项新的研究，在这里，导致我们现在提出一个统一的睡眠依赖性记忆巩固假说，描述睡眠阶段如何有助于记忆巩固。我们认为，睡眠在记忆处理中扮演的角色比以前认为的更加微妙，睡眠阶段选择性地参与记忆巩固过程的特定组成部分，而不是特定的记忆类型。具体来说，我们认为SWS稳定了最近获得的陈述性和程序性记忆，而REM和第二阶段非REM睡眠随后增强了它们，选择性地加强了它们最有价值的成分，并将它们整合到预先存在的存储信息网络中。正如我们将在下面展示的那样，这个新的假设与越来越多的关于睡眠依赖性巩固在一系列记忆功能中的文献是一致的，并且得到了我们的初步结果的有力支持。这些新的结果，与统一的记忆巩固假说相一致，使睡眠和记忆的研究超越了经典记忆巩固的讨论（即，睡眠依赖性记忆增强的更强大和更有价值的形式，（i）扩大存储记忆的神经网络，（ii）从大量编码信息中提取模式和规则，以及（iii）将它们与其他较旧的记忆整合到丰富的语义网络中，从而选择性地增强对生物体最有价值的记忆的那些方面。在下面提出的研究计划中，我们将通过综合研究来验证我们的统一的睡眠依赖性记忆巩固假设，这些综合研究旨在确定（1）睡眠期间巩固的记忆类型，（2）睡眠阶段与其稳定性和各种形式的增强（例如整合，规则提取）的相关性，以及（3）这些过程的生理基础。

DESCRIPTION (provided by applicant): The last decade has seen a dramatic increase in our understanding of sleep-dependent memory consolidation, moving it from a generally discredited (or at best ignored) concept to a largely accepted tenet among both memory and sleep researchers, even found in undergraduate psychology textbooks. This work has established a firm connection between sleep and memory function. But given the complexity of both sleep and memory, each of which comprise multiple stages and subtypes, even the most basic characterizations of this phenomenon remain unclear. Which types of memory are consolidated during sleep? Which components of consolidation occur during sleep? Which sleep stages mediate this consolidation? And what physiological processes underlie sleep-dependent consolidation? To date, most studies have sought to assign consolidation of particular classes of memory to discrete sleep stages, for example consolidation of procedural memories to REM sleep or declarative memories to slow wave sleep (SWS). But exceptions to this simple dichotomy come close to outnumbering supporting studies. Several new studies, presented here, lead us to now propose a unified sleep-dependent memory consolidation hypothesis, to describe how sleep stages contribute to memory consolidation. We propose that sleep plays a more nuanced role in memory processing than previously considered, with sleep stages being selectively involved not with specific memory types, but with specific components of the memory consolidation process. Specifically, we propose that SWS stabilizes recently acquired declarative and procedural memories, while REM and Stage 2 nonREM sleep subsequently enhance them, selectively reinforcing their most valuable components and integrating them into preexisting networks of stored information. As we will show below, this new hypothesis is consistent with the growing literature of sleep-dependent consolidation across a range of memory functions, and is strongly supported by our Preliminary Results. These new results, in concert with the unified memory consolidation hypothesis, move the study of sleep and memory beyond a discussion of classical memory consolidation (i.e., stabilization), into the realm of more powerful and valuable forms of sleep-dependent memory enhancement that (i) enlarge the neural networks in which memories are stored,(ii) extract patterns and rules from large bodies of encoded information and (iii) integrate them with other, older memories into rich semantic networks, thereby selectively enhancing those aspects of memories of greatest value to the organism. In the research program proposed below, we will test our unified sleep-dependent memory consolidation hypothesis through integrated studies designed to identify (1) the types of memories consolidated during sleep, (2) the sleep stage correlates of both their stabilization and their various forms of enhancement (e.g. integration, rule extraction) and (3) the physiological substrates of these processes.