Mechanisms of Working Memory Capacity Limits and Their Development

项目摘要/摘要 背景：工作记忆(WM)是保留在活动状态中供使用的有限信息 持续的认知。从6岁到14岁，WM的进步对儿童的多样性至关重要 认知功能，如推理、解决问题和语言。当教孩子们(典型或 挑战)，人们对如何考虑WM限制知之甚少，因为我们还不清楚 影响典型口碑发展的因素有很多。P.I.在GRANT R01-HD-21338下的研究表明 已经提出的关于WM发展的描述不充分(例如，在忽略方面的改进 分心或项目熟悉度)。我们已经用方法证明了这一点，在这些方法中，有问题的因素 以新的方式进行实验控制(例如，观察到容量增长不受任何分心或 熟悉度效应)。在我的理论框架中，WM容量限制来自于项目的数量 同时保持在关注的焦点，并有足够的细节来指导回应。在一个新的发展中 假设在该帐户中，WM项的数量可能保持不变，但WM在丰富的 项目内的特征和项目间注意到的模式。年龄较大的儿童和成年人将使用功能和 模式，以最大限度地减少对WM项目的关注。研究目标是评估这一假说。 利用新的双集(例如，视听)识别任务的变体，以识别注意力、模式 以及典型的发育儿童和年轻人的特征。具体目标是揭示这些基础 口碑的发展有四个方面。(1)我们评估是否不仅仅是WM中的物品或对象的数量 增加了开发，但其特征表示的完备性。(2)鉴于我们以前的做法 工作证明了在WM中普遍注意保留信息的重要性，我们探索了一个因素 可能会解放更成熟的参与者的注意力。年龄较大的儿童可能会快速形成图案，并 背诵“卸载”注意力以外的材料，解放注意力，以便后续输入和 WM维护。我们检查材料中的额外结构是否允许年幼的孩子卸载 更像是老一辈的。(3)我们最近发现，声音列表和语言列表(单词或 音调)比视觉阵列多得多，减少了声学物品和其他物品之间的干扰。我们会 调查这些耐人寻味的发现的基础。可能，有色斑点的顺序列表，如声学 序列，将允许比斑点阵列更好的卸载。我们还将检查振动触觉 序列与视觉对象争夺注意力的竞争比声学项目更多。最后，(4)我们采用 最近成人工作中的实验技术，以确定注意力依赖和注意力自由 这两种机制都在a)增加WM中的条目数量，或b)增加条目方面发展相似 精确度；它们的机制可能不同。影响：认知应该如何参与到教育儿童中 解决学习障碍依赖于工作记忆发展的基本机制，我们必须揭示这一点。

PROJECT SUMMARY/ABSTRACT BACKGROUND: Working memory (WM) is the limited information retained in an active state for use in ongoing cognition. Improvements in WM from 6-14 years are critically important for how children do diverse cognitive functions like reasoning, problem-solving, and language. When teaching children (typical or challenged), little is known about how to take into account WM limits because we do not yet understand what factors contribute to typical WM development. Research by the P.I. under Grant R01-HD-21338 shows that accounts of WM development that have been proposed are insufficient (e.g., improvement in ignoring distraction or in item familiarity). We have shown this using methods in which the factors in question were experimentally controlled in new ways (e.g., capacity growth was observed independent of any distraction or familiarity effects). In my theoretical framework, WM capacity limits come from how many items can be retained concurrently in the focus of attention with enough detail to guide responses. In a new developmental hypothesis within that account, the number of WM items may remain fixed but WM develops in the richness of features within items and patterns noticed across items. Older children and adults would use features and patterns to minimize the need for attention to WM items. The RESEARCH GOAL is to assess this hypothesis with variants of new dual-set (e.g., visual+acoustic) recognition tasks, to identify roles of attention, patterns, and features in typically developing children and young adults. SPECIFIC AIMS are to uncover these bases of WM development in four ways. (1) We assess whether it is not just the number of items or objects in WM that increases in development, but the completeness of their feature representations. (2) Inasmuch as our previous work demonstrated the importance of general attention to retain information in WM, we explore a factor that may free up attention in more mature participants. Older children may engage in rapid pattern formation and memorization to “off-load” materials out of the focus of attention, freeing attention for subsequent input and WM maintenance. We examine whether extra structure in the material allows younger children to off-load more like older ones do. (3) We recently found that off-loading occurs for acoustic and verbal lists (words or tones) much more than for visual arrays, reducing interference between acoustic items and other items. We will investigate the basis of these intriguing findings. Possibly, sequential lists of colored spots, like acoustic sequences, will allow better off-loading than do arrays of spots. We also will examine whether vibrotactile sequences compete with visual objects for attention, more than do acoustic items. Last, (4) we adopt experimental techniques from recent adult work to determine whether attention-dependent and attention-free mechanisms both develop similarly in terms of a) an increased numbers of items in WM, or b) increased item precision; their mechanisms may differ. IMPACT: How cognition should be engaged in educating children and addressing learning disorders depends on basic mechanisms of WM development, which we must uncover.