ELECTROPHYSIOLOGICAL MEASURES OF HUMAN MEMORY FUNCTIONS

这个项目的主要长期目标是促进我们对人类记忆的神经认知基础的理解。正在研究的中央记忆功能是那些负责成功回忆个人经历的功能。情景记忆缺陷在神经和精神障碍以及正常衰老中非常常见。然而，要找到更好的方法来治疗记忆困难的人，关键的一步是了解健康人记忆功能的神经认知结构。这项研究的前提是，在情景回忆发生时，可以通过监控其构成过程的方法来最有效地研究情景回忆。换句话说，必须使用与相关神经计算相对应的神经生理学测量，才能最终破译正常和紊乱的人类记忆的大脑底物。这项拟议的研究计划包括9项实验，旨在利用健康志愿者头皮电极上的脑电位非侵入性记录来研究一系列情景记忆功能。这些事件相关电位(ERPs)似乎对负责有效编码和提取存储信息的过程敏感，正如第一个奖项支持的先前几项研究所表明的那样。这些研究中的许多使用了记忆测试，在这些测试中，受试者没有被明确询问他们的记忆力。这些内隐记忆测试表明，一些记忆功能与那些引起情景回忆的功能是分开的。因此，内隐记忆和回忆之间的对比在认知和神经机制方面都是非常有用的。因此，来自大脑的电子记录将被用来监控负责回忆和内隐记忆的记忆功能，提供独立的记忆处理测量，其时间分辨率是目前研究人脑活动的任何现有方法所无法比拟的。还将使用两种补充方法来支持神经解剖学理论：功能磁共振成像(在建议的实验中的两项)和脑电源建模。这组实验的结果将阐明一套索引特定记忆过程的神经测量方法。这三个具体目标是：(1)提供证据，支持大脑电活动的测量可以用来监控几种有助于情景记忆的功能的想法；(2)直接对比情景记忆的ERP相关性和内隐记忆的ERP相关性；以及(3)将人类大脑功能测量的数据应用于当前巩固和提取的神经生物学模型。

The major long-term objective of this project is to advance our understanding of the neurocognitive foundations of human memory. The central memory functions under study are those responsible for the successful recollection of personally experienced episodes. Deficits in episodic memory are extremely common in neurological and psychiatric disorders and in normal aging. However, a critical step towards finding better ways to treat people with memory difficulties is to understand the neurocognitive structure of memory functions in healthy individuals. The proposed research rests on the premise that episodic recollection can be most effectively studied by using methods to monitor the constituent processes as they occur. In other words, neurophysiological measures that correspond to relevant neural computations must be used in order to ultimately decipher the brain substrates of normal and disordered human memory. The proposed research plan includes 9 experiments designed to investigate a range of episodic memory functions using noninvasive recordings of brain potentials from scalp electrodes in healthy volunteers. These event-related potentials (ERPs) appear to be sensitive to processes responsible for effectively encoding and retrieving stored information, as shown in several prior studies supported by the FIRST award. Many of these studies used memory tests in which subjects were not explicitly queried about their memories. These implicit memory tests show that some memory functions are separate from those that give rise to episodic recollection. Contrasts between implicit memory and recollection can thus be extremely informative with respect to both cognitive and neural mechanisms. Accordingly, electrical recordings from the brain will be used to monitor memory functions responsible for both recollection and implicit memory, providing independent measures of memory processing with a temporal resolution unsurpassed by any currently available method for studying the human brain in action. Two supplemental methods will also be used to support neuroanatomical theorizing: functional magnetic resonance imaging (in 2 of the proposed experiments) and brain electrical source modeling. Results from this set of experiments will elucidate a set of neural measures that index specific memory processes. The 3 specific aims are: (1) to provide evidence supporting the idea that measures of the electrical activity of the brain can be used to monitor several functions that contribute to episodic recollection; (2) to directly contrast ERP correlates of episodic recollection and ERP correlates of implicit memory; and (3) to bring data on measures of brain function in human subjects to bear on current neurobiological models of consolidation and retrieval.