How special is sleep for human memory consolidation?

背景：大量证据表明，睡眠在巩固记忆方面起着重要的，也许是关键的作用。然而，尽管表面上有压倒性的证据，睡眠记忆假说仍然面临着源源不断的批评和相互矛盾的证据。例如，许多被认为介导突触记忆巩固的可塑性机制（例如，再激活和神经元重放，缓慢振荡）也在清醒期间起作用，尽管速率较低。特别是，安静清醒状态（QW）似乎与睡眠在激活巩固机制方面有相似之处。然而，几乎所有的实证研究都使用主动清醒（AW）作为睡眠的比较条件，这可能会放大睡眠和清醒之间在记忆巩固方面的明显差异。 拟议的实验对睡眠和不同类型的觉醒的作用进行了系统的分析，重点是AW和QW在促进人类记忆巩固方面的潜在差异。提出了四个目标（O）：O1：建立并明确对比午睡，AW和QW在外显和内隐记忆巩固中的作用。 O2：比较在小睡、AW和QW期间感觉线索引起的记忆再激活的有效性。注意，感官（例如，在学习和随后的睡眠期间存在的（听觉的）线索增强了记忆巩固，这可能是通过触发与学习相关的神经元活动的再激活。 O3：确定脑电图（EEG）和睡眠阶段与记忆巩固、午睡、AW和QW的相关性。O4：评估记忆诱导和生物反馈对影响EEG活动和增强记忆巩固的有效性。在O3结果的指导下，使用声学刺激或生物反馈程序来增强与有效巩固相关的EEG频带中的活动。 重要性：AW、QW和睡眠之间的巩固的直接比较提供了一个强有力的假设检验，即睡眠在记忆巩固中起着专门或关键的作用，而不是睡眠仅仅沿着一系列行为状态，这些行为状态在有效性上各不相同，以允许在人脑中有效巩固。因此，拟议的工作将为不同行为状态的功能提供新的重要见解，以允许人类神经系统中的有效存储和长期记忆。重要的是，在拟议的研究中涉及的实验和分析工作提供了一个丰富的培训环境，在所有级别的HQP（本科到博士）。学生），谁将在确定实验设计和假设，收集，分析和解释数据的过程中发挥关键作用，以及以研讨会，会议演示和同行评议的期刊出版物的形式交流实验结果。

Background:A plethora of evidence suggests that sleep plays an important, perhaps critical role in the consolidation of memories. However, despite the seemingly overwhelming evidence, the sleep-memory hypothesis has faced a steady stream of critical commentaries and contradictory evidence. For example, many of the plasticity mechanisms thought to mediate synaptic memory consolidation (e.g., reactivation and neuronal replay, slow oscillations) also operate during wakefulness, albeit at a lower rate. In particular, the state of quiet waking (QW) appears to share similarities with sleep in terms of the activation of consolidation mechanisms. However, almost all empirical studies use active waking (AW) as a comparison condition for sleep, which may amplify the apparent differences between sleep and waking in terms of memory consolidation.  The proposed experiments perform a systematic analysis of the role of sleep and different types of waking, focusing on the potential differences between AW and QW in their effectiveness to promote memory consolidation in humans. Four objectives (O) are proposed:  O1: Establish and explicitly contrast the role of napping, AW, and QW in explicit and implicit memory consolidation. O2: Compare the effectiveness of sensory cue-elicited memory reactivation during napping, AW, and QW. Note that sensory (e.g., auditory) cues present during learning and subsequent sleep enhance the memory consolidation, presumably by triggering reactivation of learning-related neuronal activity. O3: Identify electroencephalographic (EEG) and sleep-stage correlates of memory consolidation napping, AW, and QW. O4: Assess the effectiveness of auditory-entrainment and biofeedback to influence EEG activity and enhance memory consolidation. Guided by the results of O3, acoustic stimuli or biofeedback procedures are used to enhance activity in the EEG frequency bands linked to effective consolidation. Significance: A direct comparison of consolidation between AW, QW, and sleep provides a powerful test of the hypothesis that sleep plays a specialized or critical role in memory consolidation, as opposed to sleep merely falling along a continuum of behavioral states that vary in the effectiveness to permit effective consolidation in the human brain. Thus, the proposed work will provide new and important insights into the functions of different behavioural states to allow the effective storage and long-term memories in the human nervous system. Importantly, the experimental and analytic work involved in the proposed research provides a rich training environment for HQP at all levels (undergraduate to Ph.D. students), who will play critical roles in the process of determining experimental designs and hypotheses, the collection, analysis, and interpretation of data, as well as the communication of  experimental findings in the form of seminars, conference presentations, and peer-reviewed journal publications.