The Distinction Between Number and Resolution in Visual Working Memory

描述(由申请人提供)：工作记忆(WM)是一种在几乎所有外显认知过程(如记忆提取、问题解决)中维护在线信息表征的系统。工作记忆在认知中的核心作用也被工作记忆能力和液态智力作为衡量学业成绩的各种指标之间的强烈相关性所突显。此外，WM表现的缺陷与普遍的临床疾病有关，包括注意力缺陷/多动障碍(ADHD)和精神分裂症。拟议的研究将解决与水资源管理中容量限制的基本决定因素有关的基本问题。容量是否受可以同时在WM中表示的最大项目数的限制？或者，它是否受到表示给定项目集所需的可用助记分辨率(即清晰度)的限制？我们的初步数据表明，数字和分辨率不是由单一因素决定的，而是WM能力的不同方面。这项拟议的研究试图进一步详细说明这两个因素如何通过心理物理程序、人类电生理记录(ERPs)和使用功能磁共振的新的神经解码技术的组合来限制WM的性能。本项目将侧重于关于数量和分辨率因素如何决定水资源管理能力的四个关键问题。首先，我们将研究个体的数量和分辨率限制是特定于刺激的，还是反映了更多的刺激一般限制。其次，我们将探索个体如何自愿控制这两种有限内存资源的分配。第三，我们将测量个体对可能的目标位置的隐含知识如何影响WM容量的分配。最后，我们将使用多体素模式分析(MVPA)对神经成像数据进行评估，以评估大脑皮质的视觉感觉区域如何被招募来帮助在WM中表示信息，以及它们是否有助于确定个人的助记分辨率。因此，这项研究的总体目标是更精细地刻画工作记忆中容量限制的性质，并进一步刻画控制进入这个有限的心理工作空间的机制。对这些基本研究问题的更好理解将使人们能够更准确地描述涉及认知加工障碍的精神病理学，支持心理健康领域的基础研究和翻译研究。

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 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 project will focus on four critical questions regarding how the factors of number and resolution determine WM capacity. First, we will examine whether number and resolution limits for an individual are stimulus-specific or whether they reflect more stimulus-general limitations. Second, we will explore how individuals can voluntarily control the allocation of these two limited memory resources. Third, we will measure how an individual's implicit knowledge about likely target locations can influence the allocation of WM capacity. Finally, we will use multi-voxel pattern analysis (MVPA) on neuroimaging data to assess how visual sensory areas of cortex are recruited to help represent information in WM and whether they help to determine an individual's mnemonic resolution. Thus, the general goal of this research is to more finely characterize the nature of capacity limits in WM, and to further characterize the mechanisms that control access to this limited mental workspace. 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.