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扮演着重要的、或许是关键的角色。然而，尽管似乎有压倒性的证据，睡眠记忆假说却面临着源源不断的批评评论和相互矛盾的证据。例如，许多被认为调节突触记忆巩固的可塑性机制(例如，重新激活和神经元重放，慢振荡)也在清醒时起作用，尽管速度较低。特别是，在激活巩固机制方面，安静清醒状态(QW)似乎与睡眠有相似之处。然而，几乎所有的经验研究都使用主动觉醒(AW)作为睡眠的比较条件，这可能会放大睡眠和清醒在记忆巩固方面的明显差异。建议的实验对睡眠和不同类型的觉醒的作用进行了系统分析，重点是AW和QW在促进人类记忆巩固方面的潜在差异。四个目标(O)被提出：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：比较在午睡、AW和QW过程中感觉线索引起的记忆重新激活的有效性。注意，在学习和随后的睡眠中出现的感觉(例如，听觉)提示可能通过触发与学习相关的神经元活动的重新激活来增强记忆巩固。臭氧：确定脑电(EEG)和睡眠阶段与记忆巩固午睡、AW和QW的相关性。O4：评估听觉夹带和生物反馈对影响脑电活动和增强记忆巩固的有效性。在臭氧结果的指导下，使用声刺激或生物反馈程序来增强与有效巩固相关的脑电频段的活动。意义：对AW、QW和睡眠之间的巩固进行直接比较，可以对睡眠在记忆巩固中发挥特殊或关键作用的假设进行强有力的测试，而不是仅仅沿着一系列行为状态下降，这些状态的有效性不同，从而允许在人脑中进行有效的巩固。因此，这项拟议的工作将为不同行为状态的功能提供新的和重要的见解，以实现人类神经系统的有效存储和长期记忆。重要的是，拟议研究中涉及的实验和分析工作为各级HQP(本科生到博士生)提供了一个丰富的培训环境，他们将在确定实验设计和假设的过程中发挥关键作用，收集、分析和解释数据，以及以研讨会、会议演示和同行评议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.