The Distinction Between Number and Resolution in Visual Working Memory

描述（由申请人提供）：工作记忆（WM）是一个系统，用于维持在线表示的信息服务于几乎所有的显式认知过程（例如，记忆检索、问题解决）。工作记忆在认知中的核心作用也突出了工作记忆能力和流体智力之间的强相关性，作为学业成绩的各种措施。此外，WM表现的缺陷与流行的临床疾病相关，包括注意缺陷/多动障碍（ADHD）和精神分裂症。这项补充申请的母基金中的拟议研究将解决有关WM容量限制的基本决定因素的基本问题。容量是否受到WM中可以同时表示的最大项目数的限制？或者它受到可用助记符解析的限制（即，清晰度）表示给定的一组项目所必需的？我们的初步数据表明，数量和分辨率不是由单一因素决定的，而是WM能力的不同方面。拟议的研究旨在进一步详细说明这两个因素如何相互作用，以限制WM性能的心理物理程序，人类电生理记录（ERP），和新的神经解码技术，使用功能磁共振成像的组合。该补充申请通过大规模的个体差异研究扩展了母项目的范围，该研究考察了WM能力与流体智力标准测量之间关系的性质（例如，斯坦福大学比奈智商）。鉴于工作记忆能力和流动智力之间的联系是工作记忆研究的一个核心激励因素，人们高度重视能够阐明为什么这些联系首先存在的研究。我们的初步研究结果表明，虽然WM中可以持有的表征数量强烈预测流体智力，但这些记忆的精确度或分辨率与智力无关。我们将使用更广泛的记忆和智力能力的行为和神经测量来复制和扩展这一结果，目的是更好地理解智能行为是如何由较低水平的记忆过程支持的。这个项目将告知两个认知模型的WM是如何组织跨刺激方式，以及WM功能的精确方面，影响流体智力的个体差异。更好地理解这些基础研究问题将使涉及受损的认知处理的精神病理学的更精确的表征，支持在心理健康领域的基础和转化研究。 公共卫生相关性：该提案概述了一个补充项目，该项目扩大了父母资助项目的范围，其主要目的是更好地描述人类工作记忆能力限制的性质。这个记忆系统是大多数认知过程的核心部分，这个系统的容量与流体智力和学业成绩相关。补充提案的重点是工作记忆和流体智力之间的关系，跟进初步发现，虽然一个人可以在工作记忆中保持的项目数量强烈预测流体智力，但在存储的记忆和智力之间没有观察到这种关系。鉴于工作记忆和智力能力的广泛测量之间的关系构成了这一领域研究的核心动机，更好地理解基本记忆过程如何支持智能行为是非常可取的。拟议的研究通过描述为什么可以存储在工作记忆中的项目数量与流体智力有关，并为视觉工作记忆的广泛分类提供进一步的证据来实现这一目标。

DESCRIPTION (provided by applicant): Working memory (WM) is a system for maintaining online representations of information in the service of virtually all explicit cognitive processes (e.g., memory retrieval, problem solving). WM's core role in cognition is also highlighted by strong correlations between WM capacity and fluid intelligence as various measures of scholastic achievement. Furthermore, deficits in WM performance are associated with prevalent clinical disorders, including attention deficit/ hyperactivity disorder (ADHD) and schizophrenia. The proposed research in the parent grant to this supplemental application will address fundamental questions regarding the basic determinants of capacity limits in WM. Is capacity limited by a maximum number of items that can be represented simultaneously in WM? Or is it limited by the available mnemonic resolution (i.e., clarity) necessary for representing a given set of items? Our preliminary data suggest that rather than being determined by a single factor, number and resolution are distinct facets of WM capacity. The proposed research seeks to further detail how these two factors interact to limit WM performance by means of a combination of psychophysical procedures, human electrophysiological recordings (ERPs), and novel neural decoding techniques using FMRI. This supplemental application expands the scope of the parent project by means of a large- scale individual differences study that examines the nature of the relationship between WM capacity and standard measures of fluid intelligence (e.g., Stanford Binet IQ). Given that the link between WM capacity and fluid intelligence is a core motivating factor for WM research, high value is placed on research that can elucidate why these links are present in the first place. Our preliminary findings indicate that while the number of representations that can be held in WM strongly predicts fluid intelligence, the precision or resolution of those memories showed no correlation with intelligence. We will replicate and extend this result using a broader range of behavioral and neural measures of memory and intellectual ability, with the goal of better understanding how intelligent behavior is supported by lower level memory processes. This project will inform both cognitive models of how WM is organized across stimulus modalities, and the precise aspects of WM function that influence individual variations in fluid intelligence. A better understanding of these basic research questions will enable a more precise characterization of psychopathologies that involve impaired cognitive processing, supporting both basic and translational research in the domain of mental health. PUBLIC HEALTH RELEVANCE: This proposal outlines a supplemental project that expands the scope of a parent grant project whose broad aims are to better characterize the nature of capacity limits in human working memory. This memory system is a core part of most cognitive processes, and capacity in this system is correlated with fluid intelligence and scholastic achievement. The supplemental proposal focuses on the relationship between working memory and fluid intelligence, following up on preliminary findings that while the number of items a person can maintain in working memory strongly predicts fluid intelligence, no such relationship was observed between the precision of the stored memories and intelligence. Given that the relationship between working memory and broad measures of intellectual ability constitute a core motivation for research in this area, a better understanding of how basic memory processes support intelligent behavior is highly desirable. The proposed research accomplishes this goal by characterizing why the number of items that can be stored in working memory relates to fluid intelligence, and providing further evidence on the broad taxonomy of visual working memory.