Mechanisms of Working Memory Capacity Limits and Their Development

项目总结/摘要 背景：工作记忆是一种处于活跃状态的有限信息， 持续认知从6-14岁的WM的改善是至关重要的儿童如何做不同的 认知功能，如推理，解决问题和语言。当教孩子（典型或 挑战），很少有人知道如何考虑WM限制，因为我们还不知道什么是WM限制。 因素有助于典型的WM发展。P.I.的研究根据格兰特R 01-HD-21338显示， 已经提出的WM发展的说明是不充分的（例如，忽略的改进 分心或在项目熟悉度）。我们已经证明了这一点，使用的方法中，所讨论的因素是 以新的方式进行实验控制（例如，观察到容量增长独立于任何分心或 熟悉效应）。在我的理论框架中，工作记忆容量的限制来自于有多少项目可以 同时保持在关注的焦点，有足够的细节来指导反应。在一个新的发展 假设在帐户中，WM项目数量可能保持固定，但WM发展丰富， 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人将使用功能， 模式，以尽量减少对WM项目的关注。本研究的目的是评估这一假设 利用新的对偶集的变体（例如，视觉+听觉）识别任务，以识别注意力的作用，模式， 并且在典型发育的儿童和年轻人中具有特征。具体目标是揭示这些基础， 四种方式的WM开发。(1)我们评估是否不仅仅是工作记忆中的项目或对象的数量， 增加的发展，但其功能表示的完整性。(2)由于我们以前的 工作证明了一般注意力的重要性，以保持信息在工作记忆，我们探讨了一个因素， 可以释放更成熟参与者的注意力。年龄较大的儿童可能会进行快速的模式形成， 记忆，以“卸载”材料的注意力的焦点，释放注意力，为后续的输入， WM维护。我们研究材料中的额外结构是否允许年幼的孩子卸载 更像年长的人(3)我们最近发现，卸载发生在声学和口头清单（单词或 音调）比视觉阵列多得多，减少了声学项目和其他项目之间的干扰。我们将 研究这些有趣发现的基础。有可能，彩色斑点的顺序列表，如声学 序列，将允许比点阵列更好的卸载。我们还将研究振动触觉 序列与视觉对象竞争注意力，比声学项目更多。最后，（4）我们采用 从最近的成人工作的实验技术，以确定是否注意依赖和注意自由 两种机制的发展相似，a）WM中项目数量增加，或B）项目增加 精确度;它们的机制可能不同。影响：认知应该如何参与教育儿童 而解决学习障碍依赖于工作记忆发展的基本机制，这是我们必须揭示的。

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.