The flexibility of individuation and ensemble representation

描述(由申请人提供)：视觉工作记忆是一种基本的认知资源，对视觉空间推理、眼动引导和感知随时间的稳定性至关重要。以往关于视觉工作记忆的研究大多集中在其容量限制上，普遍认为视觉工作记忆一次最多只能存储3到4个个性化物体的详细视觉信息。另一个单独的研究机构专注于存储来自对象集合的平均特征的较低分辨率表示(集合表示)的并行能力-但很少有工作探索两者之间的联系，它们通常被视为视觉研究中的单独主题。相比之下，这项拟议的研究评估了关于这两种视觉表征模式如何相互关联的两种相互竞争的假设。灵活表征模型预测视觉系统可以灵活地在个性化表征和整体表征之间交替，可以说，选择在任何给定时间最合适的表征类型。封装的表示模型认为，这些表示模式是自动的、不灵活的，两种模式总是并行发生的。TE提出的研究评估了这两个模型，依赖于记忆精确度的行为和神经特征来确定在(在灵活表征模型下)应该有利于存储集合而不是个体的条件下，个性化是否减少(和集合表征增强)。这些研究将使用EEG/ERP来测量个性化的所谓神经特征-对侧延迟活动(CDA)，并将有助于揭示该信号是真正反映了个性化的物体样表征，还是更灵活的、分层结构的表征。关键的是，拟议的研究旨在产生一个 最终的结果--证实了灵活的模型或封装的模型--在任何一种情况下都将代表着视觉记忆文献的重大进步。这些研究也可能揭示先前记录的自闭症谱系障碍(ASD)的视觉处理缺陷。具体地说，先前的研究表明，自闭症患者在全局或整体感知方面存在困难，但在涉及狭隘焦点或精确表示部分的任务中，似乎比典型的发展型个人表现得更好。如果我们的研究证实了灵活表征模式，这将表明这些效应背后存在更根本的损害--自闭症患者的灵活性可能受到损害，即使在他们应该形成整体表征的时候也会个性化。最后，本研究将为申请者提供视觉记忆和事件相关电位研究方面的重要培训。虽然申请人以前研究过视觉注意和知觉，但他没有广泛地研究过视觉工作记忆，也没有做过脑电/事件相关电位的研究。因此，该项目的这两个方面都是关键培训，将扩大申请人的研究技能范围。

DESCRIPTION (provided by applicant): Visual working memory is a fundamental cognitive resource, critical for visuospatial reasoning, guidance of eye movements, and the stability of perception over time. Much of the previous research on visual working memory has focused on its capacity limitations, with a general consensus that visual working memory can store detailed visual information from at most 3 or 4 individuated objects at any one time. A separate body of research has focused on a parallel capacity for storing lower-resolution representations of average features (ensemble representations) derived from collections of objects - but not much work has explored connections between the two, and they are often treated as separate topics in vision research. By contrast, the proposed research evaluates two competing hypotheses about how these two modes of visual representation relate to one another. The Flexible Representation model predicts that the visual system can flexibly alternate between individuation and ensemble representation, choosing, as it were, the type of representation most appropriate at any given time. The Encapsulated Representation model holds that these modes of representation are automatic and inflexible, with both occurring in parallel, all of the time. Te proposed studies evaluate these two models, relying on behavioral and neural signatures of memory precision to determine whether individuation is reduced (and ensemble representation enhanced) under conditions that should (under the Flexible Representation model) favor storing ensembles rather than individuals. These studies will use EEG/ERP to measure a purported neural signature of individuation - the contralateral delay activity (CDA), and will help reveal whether this signal truly reflects individuated object-like representations, or more flexible, hierarchically structured representations. Critically, the proposed studies are designed to yield a definitive result - confirming either the Flexible model or the Encapsulated model - and will represent a major advance in the visual memory literature in either case. These studies may also shed light on previously-documented visual processing deficits in autism spectrum disorder (ASD). Specifically, prior research has shown that ASD individuals have difficulty with global or holistic perception, but seem to be better than typically-developing individuals at tasks that involve narrow focus or precise representations of parts. If our studies confirm the Flexible Representation model, this would suggest a more fundamental impairment underlying these effects - ASD individuals may have impaired flexibility, individuating even when they should be forming ensemble representations. Finally, this research will provide the applicant with vital training in both visual memory and ERP research. While the applicant has previously studied visual attention and perception, he has not extensively studied visual working memory, nor has he previously done EEG/ERP research. Thus, both aspects of the project represent critical training that will broaden the scope of the applicant's research skillset.