Effects of Repetition on Learning and Memory in Amnesia

描述（由申请人提供）：该提案代表了对健忘症患者重复学习和记忆影响的系统研究。虽然很明显，重复是增强健忘症患者记忆的最有效方法之一，但我们对哪种重复最有益，以及不同形式的重复产生效果的机制知之甚少。目前的研究是由一个框架，区分由内侧颞叶介导的快速学习系统和由新皮层介导的缓慢学习系统，并基于重复在这些系统中的每一个有不同的效果的假设。该提案的第一部分通过评估遗忘症患者的三种不同机制的运作来检查快速内侧颞叶学习系统中的重复，这些机制被认为有助于记忆功能完整的个体的重复效应，即（1）编码;（2）工作记忆中的时间;（3）学习阶段提取。我们预测，这些机制将在健忘症患者中受损，但可以创造条件，最大限度地减少这些损伤，从而优化其性能。第二部分的建议涉及的影响，重复在缓慢的新皮层学习系统。关于慢学习系统中重复的性质和特征知之甚少，因为以前的研究未能将慢的新皮层学习的贡献与快的内侧颞叶学习的贡献分开。在这里，我们利用一种新的范式，允许评估缓慢的新皮层学习系统的隔离和测试的假设，这种学习是完整的健忘症患者。我们还研究了各种编码和检索条件如何影响基于重复的缓慢学习，目的是揭示如何在健忘症患者中优化这种学习。更好地理解重复在快速和慢速学习系统中的运作方式，将阐明这些记忆系统的运作，并为开发旨在增强健忘症中不同形式记忆的特定策略提供理论基础。

DESCRIPTION (provided by applicant): This proposal represents a systematic investigation of the effects of repetition on learning and memory in amnesic patients. Although it is clear that repetition provides one of the most powerful methods to enhance memory in amnesia, little is known about the kinds of repetition that are most beneficial, and the mechanisms by which different forms of repetition have their effect. The present studies are guided by a framework that distinguishes between a fast learning system mediated by the medial temporal lobes and a slow learning system mediated by neocortex, and are based on the assumption that repetition has distinct effects in each of these systems. The first section of the proposal examines repetition in the fast medial temporal learning system by evaluating the operation in amnesic patients of three different mechanisms thought to contribute to repetition effects in individuals with intact memory function, namely (1) encoding; (2) time in working memory; and (3) study-phase retrieval. We predict that these mechanisms will be impaired in individuals with amnesia, but that conditions can be created that minimize these impairments, thus optimizing their performance. The second section of the proposal concerns the effects of repetition in the slow neocortical learning system. Little is known about the nature and characteristics of repetition in the slow learning system, because previous studies have failed to isolate the contribution of slow neocortical learning from that of fast medial temporal learning. Here we make use of a novel paradigm that allows assessment of the slow neocortical learning system in isolation and test the hypothesis that such learning is intact in amnesic patients. We also examine how various encoding and retrieval conditions affect repetition-based slow learning, with the aim of uncovering how such learning can be optimized in amnesic patients. A better understanding of the ways in which repetition operates within the fast and the slow learning systems will elucidate the operation of these memory systems and will provide a theoretical basis for the development of specific strategies aimed at enhancing distinct forms of memory in amnesia.