ELECTROPHYSIOLOGICAL MEASURES OF HUMAN MEMORY FUNCTIONS

这项研究的主要目的是增进我们对 负责人类记忆的大脑机制。主存 正在研究的功能是负责情景回忆的功能， 用于执行回忆和识别的标准测试的一种内存类型。 器质性记忆障碍的神经心理学研究结果 被用来(A)确定对此至关重要的大脑结构 记忆功能和(B)表明情节回忆是生物学上的 可与其他类型的内存区分开来-这一见解提供了 为拟议的实验奠定了关键基础。这些实验利用了 一种允许电生理关联发作的新技术 从神经学正常的脑电记录中获得的记忆 研究对象。有了这项技术，就有可能监测记忆在 没有任何同时存在的行为迹象表明这一点。 录音是在单词以显式或隐式方式呈现时进行的 内存测试条件。其中一些单词也在前面的 实验，但在内隐记忆测试中，受试者不被告知 这一记忆正在接受测试。这些方面的专门绩效衡量标准 内隐记忆测试对前一词的影响很敏感 陈述，这一结果被称为“启动”。此外，受试者 在这种情况下，经常进行“附带回忆”， 它被定义为任务指令不要求的回忆。这个 受试者进行有意识回忆的程度可以是 使用各种实验程序进行系统控制。 行为测量表明，某些程序会影响回忆 和识别，但不影响启动，而其他程序 产生相反的模式。这些记忆分离支持 回忆和启动是两种不同类型的记忆。 此外，初步结果表明，回忆与 记录的脑电活动的明显模式 头皮。启动与另一种脑电模式有关 发生在较早延迟且更集中的活动 分布在枕部大脑区域，与事实一致 启动发生在视觉通道内。进一步的实验将 重点关注三个具体目标：(1)提供一致的证据 几种实验方法支持有意识的观点 回忆与可测量的电生理标记物相关， (2)确定这种现象是否是一般性的，可以 使用内隐或外显记忆测试，听觉或视觉 刺激、语言或图片信息等；以及(3) 回忆性电生理检查的比较与对比 进程与与启动相关的进程进行比较，以了解更多有关 这两种类型的记忆和负责神经之间的区别 机械装置。这些新的在线电活动测量 因此，伴随的回忆和启动将有助于监测 记忆功能的时间进程与更好的理解 他们的认知和神经组织。

The major objective of this research is to advance our understanding of the brain mechanisms responsible for human memory. The primary memory functions under study are those responsible for episodic recollection, the type of memory used to perform standard tests of recall and recognition. Results from neuropsychological studies of organic memory disorders have been used to (a) identify brain structures that are crucial for this memory function and (b) show that episodic recollection is biologically distinguishable from other types of memory - an insight that provides a key foundation for the proposed experiments. These experiments make use of a new technique that allows electrophysiological correlates of episodic recollection to be derived from EEG recordings in neurologically normal subjects. With this technique it is possible to monitor recollection in the absence of any concurrent behavioral indication to that effect. Recordings are made while words are presented under explicit or implicit memory testing conditions. Some of the words are also presented earlier in the experiment, but in implicit memory tests subjects are not informed that memory is being tested. Specialized performance measures in these implicit memory tests are sensitive to the influence of prior word presentations, an outcome referred to as "priming." In addition, subjects in these circumstances regularly engage in "incidental recollection," which is defined as recollection not required by task instructions. The extent to which subjects engage in conscious recollection can be systematically controlled using various experimental procedures. Behavioral measures demonstrate that certain procedures influence recall and recognition, but do not influence priming, whereas other procedures yield the opposite pattern. These memory dissociations support the conception of recollection and priming as two different types of memory. Furthermore, preliminary results showed that recollection was associated with a distinct pattern of brain electrical activity recorded from the scalp. Priming was associated with another pattern of brain electrical activity that occurred at an earlier latency and was more focally distributed over occipital brain regions, consistent with the fact that priming occurred within the visual modality. Further experiments will focus on three specific aims: (1) to provide converging evidence with several experimental methods supporting the contention that conscious recollection is associated with a measurable electrophysiological marker, (2) to determine whether this phenomenon is a general one that can be found using either implicit or explicit memory tests, auditory or visual stimuli, linguistic or pictorial information, and so on; and (3) to compare and contrast electrophysiological measures of recollective processes with those associated with priming so as to learn more about the distinction between these two types of memory and the responsible neural mechanisms. These new on-line measurements of the electrical activity accompanying recollection and priming will thus be useful for monitoring the time-course of memory functions and developing a better understanding of their cognitive and neural organization.