Memory-Induced Performance Costs in Amnesia

描述（由申请人提供）：本提案代表了对健忘症中记忆引起的性能成本的系统调查。直到最近，对健忘症患者的空闲记忆能力的研究一直集中在一次经历对后续任务表现的促进作用上。然而，最近对正常认知的研究强调了这样一个事实，即经验诱发的促进是有代价的：对一种刺激的处理增强往往伴随着对另一种刺激的处理受损。令人惊讶的是，对于健忘症患者是否以及在什么情况下表现出在正常认知中观察到的记忆诱发的表现成本，人们知之甚少。目前的研究以一个区分三种记忆诱发性能成本的框架为指导：1)那些是外显记忆过程在名义上的内隐记忆任务中运作的产物；(2)内隐记忆过程的产物和外显记忆过程的对立；3)那些是抑制控制过程的结果，增强了刺激选择，并且独立于外显记忆运作。我们预测，失忆症的表现成本将在第一种情况下受损或不存在，在第二种情况下正常或大于正常，在内侧颞叶失忆症中正常，但在第三种情况下，在Korsakoff失忆症中受损。更好地了解健忘症患者表现出或不表现出记忆诱发的性能成本的条件，将阐明健忘症中剩余记忆容量的范围和性质，并将限制有关正常认知中性能成本机制的理论。

DESCRIPTION (provided by applicant): This proposal represents a systematic investigation of memory-induced performance costs in amnesia. Until recently, investigations of spared memory capacities in amnesia have focused on the facilitatory effects that an experience can have on subsequent task performance. Recent studies in normal cognition, however, have highlighted the fact that experience-induced facilitation comes at a price: Enhanced processing of one stimulus is often accompanied by impaired processing of another. Surprisingly little is known about whether and under what conditions amnesic patients show the memory-induced performance costs that have been observed in normal cognition. The present studies are guided by a framework that distinguishes among three kinds of memory-induced performance costs: 1) those that are the product of explicit memory processes operating in nominally implicit memory tasks; 2) those that are the product of implicit memory processes and that may be opposed by explicit memory processes; and 3) those that are the consequence of inhibitory control processes that enhance stimulus selection, and that operate independently of explicit memory. We predict that performance costs in amnesia will be impaired or absent in the first instance, normal or greater-than-normal in the second instance, and normal in medial temporal-lobe amnesia but impaired in Korsakoff amnesia in the third instance. A better understanding of the conditions under which amnesic patients do or do not show memory-induced performance costs will elucidate the scope and nature of spared memory capacities in amnesia, and will constrain theories about the mechanisms underlying performance costs in normal cognition.