KDI: Discrete Representations in Working Memory: Developmental, Neuropsychological, and Computational Investigations

这个项目旨在加深我们对构成工作记忆的神经表征的理解。工作记忆指的是在解决问题和计划等复杂认知任务中主动保持信息的能力。研究人员团队研究了工作记忆系统在学习和发展过程中的独特需求如何塑造其表征，以及这些表征如何影响整个认知系统对工作记忆的使用。他们对这一过程的主要洞察来源将来自计算分析，该分析将用于整合和探索神经生物学以及发展和成人认知的相关发现。主要的假设是，为了在延迟和面对干扰的情况下保持信息的活跃状态，工作记忆表征应该是离散的。离散表示只允许可能状态的有限集合，而不是表示连续状态。例如，1到100之间的整数构成一个离散集合，与此范围内的实数形成对比。离散性使表示具有一定的稳健性，因为通过将观察到的状态解释为最接近的离散状态，可以克服少量的“噪声”。在离散性这一核心性质的基础上，还有许多其他性质。例如，离散表示应该更明确，更容易表达，更好地感知或执行一系列步骤，并且更容易被意识到。所有这些性质都有成分，提出的研究就是探索它们都遵循的更基本的性质--决定论。该项目的最初目标将通过实验研究来确定工作记忆表征确实是离散的这一假设的有效性。这将通过探索这一假设的一个关键行为后果来实现：工作记忆表征应该比其他表征更明确。这一预测将通过一系列现有的经验范式进行研究，这些范式阐明了影响工作记忆系统的变量，包括发育年龄、延迟、双重任务需求和脑损伤。工作记忆在大多数关于复杂人类行为的描述中起着核心作用，因为在任何涉及到一个暂时延长的注意力焦点的多个STO的任务中，工作记忆都是必需的。这类任务很重要，而且普遍存在于整个社会，包括：经济、政治和军事规划；空中交通管制；以及科学研究，仅举几例。了解工作记忆系统中表征的性质，以及了解人们如何学习使用工作记忆来服务于复杂的行为是至关重要的。这项研究将促进我们在这一重要领域的知识，并可能为脑损伤后工作记忆的康复技术和帮助儿童工作记忆发展的技术提供洞察力。

This project aims to futher our understanding of the neural representations that underlie working memory. Working memory refers to the active maintenance of information in the service of complex cognitive tasks such as problem solving and planning. The team of investigator with study how the unique demands placed on the working memory system shape its representations during learning and development, and how these representations affect the use of working memory by the cognitive system as a whole. Their primary source of insight into this process will come from a computational analysis, which will be used to integrate and explore relevant findings from neurobiology and developmental and adult cognition. The primary hypothesis is that to maintain information in an active state over delays and in the face of interference, working memory representations should be discrete. A discrete representation admits to only a finite set of possible states, rather than representing continuous states. For example, the integers from 1 to 100 form a discrete set, in contrast to the real numbers in this range. Discreteness imparts a measure of robustness to the representation because small amounts of "noise" can be overcome by interpreting an observed state as the nearest discrete stat. From the central property of discreteness, a number of other properties follow. For example, discrete representations should be more categorical, more easily verbalize, better for perceiving or performing a sequence of steps, and more accessible to awareness. All these properties have component of the proposed research is to explore the idea that they all follow from the more basic property of dicreteness. The initial goal of the project will be establish through experimental studies the validity of the hypothesis that working memory representations are indeed discrete. This will be done by exploring a key behavioral consequence of this hypothesis: working memory representations should be more categorical than other representations. This predicition will be investigated with a set of existing empirical paradigms that have elucidated variables that affect the working memory system, including developmental age, delay, dual-task demands, and brain damage. Working memory plays a central role in most accounts of complex human behavior, because working memory is required in any task that involves multiple stos ir a temporally extended focus of attention. This kinds of tasks are important and pervasive throughout society, including: economic, political, and military planning; air-traffic control; and scientific research, to name just a few. It is essential to understand the nature of the representations in the working memory system and to understand how people learn to use working memory in the service of complex behavior. This research will advance our knowledge in this important area, and may provide insight into techniques for rehabilitation of working memory following brain injury and techniques for assisting the development of working memory in children.