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。拟议的研究将解决关于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，而不是由一个单一的因素，数量和分辨率是不同方面的WM能力。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。这个项目将集中在四个关键的问题，关于数量和分辨率的因素如何决定WM容量。首先，我们将研究个体的数量和分辨率限制是否是刺激特定的，或者它们是否反映了更多的刺激一般的限制。其次，我们将探讨个体如何能够自愿地控制这两种有限的记忆资源的分配。第三，我们将衡量一个人的内隐知识可能的目标位置可以影响WM容量的分配。最后，我们将使用多体素模式分析（MVPA）的神经影像数据，以评估视觉感觉区的皮质是如何招募，以帮助代表WM中的信息，以及它们是否有助于确定一个人的记忆分辨率。因此，本研究的总体目标是更精细地表征工作记忆中容量限制的性质，并进一步表征控制进入这一有限心理工作空间的机制。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。

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.