Human Cerebellar Function in Multiple Task Domains

项目总结 这个项目的目标是扩大我们对小脑的了解，特别是，如何在大脑皮质下 结构有助于人类的认知。各行各业的研究提供了令人信服的证据 小脑不仅参与感觉运动控制，还参与一系列认知功能。 例如，神经成像文献已经制作了小脑的地图，展示了稳定的功能 组织，大部分小脑皮质表现出血流动力学变化，不能归因于 有动静。此外，小脑疾病患者在任务评估方面表现出行为障碍。 认知加工和情感加工。然而，我们对小脑在脑内的功能作用的理解 认知领域仍然是初级的：功能假说要么是描述性的，要么是有针对性的 以一种相对狭隘的、特定于任务的方式来解释小脑功能。中概述的研究计划 这项提议旨在解决这个问题，寻求建立一个关于小脑的机械论解释。 功能。从理论上讲，这项工作将由一个新的假设指导，即小脑是必不可少的 对于需要连续转换内部表示或CORT(连续)的处理 表象变换)。这一假说简明地解释了小脑如何 支持不同任务域中的性能。在感觉运动控制的背景下，CORT将需要 将肢体从一个位置移动到另一个位置并预测感觉所需的计算 那次运动的后果。在其他任务域中，内部任务域的持续转换 表征可以优化预期行为；例如，知觉经常涉及内部 转换感官输入以解释非典型观点，以及社会判断可能会受益 不断地模拟另一个人的预期行为。这项研究计划将涉及 综合运用行为、计算和神经成像研究。其中一个主要组成部分是 行为工作将集中在脊髓小脑性共济失调(SCA)患者的表现上。这项工作将 涉及跨越广泛任务领域的传统现场实验，以测试CORT假说，如 以及一个雄心勃勃的在线测试计划。通过一个由政制事务局局长支持的外展计划 网络和与国际研究团队的合作，在线计划应该产生一个 独一无二的数据库，可提供强大的功能假设测试，并检查 行为表现、病因学和临床分级，并将这些测量与特定区域的病理学联系起来 在小脑里。第二个主要组成部分将建立在最近对健康年轻人进行的神经成像工作的基础上 通过使用大型电池，这提供了人类小脑的全面功能图 任务的数量。这种方法将被用来探索对功能图组织的限制，方法是 开发皮质-小脑连接的模型，并检查学习过程中的变化。AS 随着神经心理学的研究，神经成像研究将产生一个丰富的数据库来评估不同的 功能假说，以及建立与非典型人群进行比较的标准。 好了！

PROJECT SUMMARY The goal of this project is to extend our understanding of the cerebellum, and in particular, how this subcortical structure contributes to human cognition. Diverse lines of research provide compelling evidence that the cerebellum is not only involved in sensorimotor control, but also contributes to a range of cognitive functions. For example, the neuroimaging literature has produced maps of the cerebellum that exhibit a stable functional organization, with much of the cerebellar cortex showing hemodynamic changes that cannot be attributed to movement. Moreover, patients with cerebellar disorders exhibit behavioral impairments on tasks assessing cognitive and affective processing. However, our understanding of the functional role of the cerebellum in cognitive domains remains rudimentary: Functional hypotheses have either been largely descriptive or targeted to account for cerebellar function in a relatively narrow, task-specific manner. The research program outlined in this proposal is designed to address this issue, seeking to develop a mechanistic account of cerebellar function. Theoretically, the work will be guided by a novel hypothesis, namely that the cerebellum is essential for processing that requires the continuous transformation of an internal representation, or CoRT(continuous representational transformation). This hypothesis offers a parsimonious account of how the cerebellum supports performance in diverse task domains. In the context of sensorimotor control, CoRT would entail computations required to move a limb from one position to another and to anticipate the sensory consequences of that movement. In other task domains, the continuous transformation of an internal representation may optimize anticipatory behavior; for example, perception frequently involves the internal transformation of the sensory input to account for atypical viewpoints, and social judgments may benefit continuously simulating the intended actions of another individual. The research program will involve the integrated use of behavioral, computational, and neuroimaging studies. One major component of the behavioral work will focus on the performance of individuals with spinocerebellar ataxia (SCA). This work will involve traditional on-site experiments spanning a broad range of task domains to test the CoRT hypothesis, as well as an ambitious on-line testing program. Through an outreach program facilitated by SCA support networks and collaborations with an international team of researchers, the on-line program should produce a unique database to provide well-powered tests of functional hypotheses, and examine relationships between behavioral performance, etiology, and clinical ratings, and relate these measures with region-specific pathology in the cerebellum. A second major component will build on recent neuroimaging work with healthy young adults that has provided a comprehensive functional map of the human cerebellum though the use of a large battery of tasks. This approach will be used to explore constraints on the organization of the functional map by developing models of cortico-cerebellar connectivity and examining changes over the course of learning. As with the neuropsychological studies, the neuroimaging studies will yield a rich database to evaluate different functional hypotheses, as well as establish norms for comparison with atypical populations. !