Cognition, Learning and Memory: A Parallel Distributed Processing Approach

本项目将考虑在理论框架发展中出现的两个主题，称为并行分布式处理（PDP）框架，用于理解学习，记忆和认知过程。在这个框架中，认知过程产生于大量简单处理单元的同时活动；控制处理的知识由单元之间连接的数值强度表示。该方法将应用于记忆信息的回忆和语言习得。从PDP的角度来看，回忆变成了一个过程，从许多先前经验的贡献中构建要记住的项目的表征。这种观点预测，在不同时间获得的信息可能会在同一回忆行为中组合在一起，从而在记忆中产生“混合”错误。项目的第一部分将验证这些错误是否会发生，并检查它们发生的情况。这些实验将检验记忆痕迹相似性的影响，将评估混合错误在识别和回忆中发生的趋势，并将确定当不同的经验相互补充而不是相互冲突时，混合错误是否会更频繁地发生。这些实验将有助于澄清记忆机制何时以及如何导致可能使目击者证词无效的错误。从PDP的角度来看，学习语言本身不是学习语言规则系统的问题；相反，这是一个调整各单位之间联系强度的问题。该项目的第二部分将检查这种观点是否与儿童习得语言的一个方面相一致，即动词屈折形式的使用（例如，过去时）。该项目的这一部分将尝试通过连接强度调整对早期的习得模型进行修订，并使用该模型来解释儿童在习得过程中所犯的错误。该项目的这一部分应该有助于阐明语言习得背后机制的本质。

This project will consider two topics that arise in the development of a theoretical framework, known as the parallel distributed processing (PDP) framework, for understanding learning, memory, and cognitive processes. In this framework, cognitive processes emerge from the simultaneous activity of a large number of simple processing units; the knowledge that governs processing is represented by the numerical strengths of connections among the units. The approach will be applied to recall of information from memory and to language acquisition. From a PDP perspective, recall becomes a process of constructing the representation of a to-be-remembered item from the contributions of a number of prior experiences. This view predicts that information acquired at different times may be combined in the same act of recall, producing "blend" errors in memory. The first part of the project will verify that such errors occur and will examine the circumstances under which they occur. The experiments will examine the effects of similarity of memory traces, will assess the tendency for blend errors to occur in recognition as well as recall, and will determine whether blend errors occur more frequently when the different experiences to be combined complement, rather than conflict, with each other. These experiments will help clarify when and how the mechanisms of memory can give rise to errors that could invalidate eyewitness testimony. From a PDP perspective, learning language is not a matter of learning a system of linguistic rules per se; rather, it is a matter of adjusting connection strengths among units. The second part of the project will examine whether this view is consistent with children's acquisition of one aspect of language, namely the use of inflected forms of verbs (e.g., the past tense). This part of the project will attempt to develop a revision of an earlier model of acquisition by connection strength adjustment and to use the model to account for errors that children make during acquisition. This part of the project should help clarify the nature of the mechanisms that underlie the acquisition of language.