Neural basis of limb selection in unimanual reaching

单手抓取肢体选择的神经基础

基本信息

批准号：
10609904
负责人：
ERIC F MOOSHAGIAN
金额：
$ 44.53万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN DIEGO
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-04-15 至 2027-02-28
项目状态：
未结题

项目摘要

Abstract The central goal of this proposal is to understand the neural systems subserving the decision to use the left or right hand1 – a simple choice that is central to our daily functions. Here we focus on parietal mechanisms of limb selection. Despite it being one of the most common decisions faced in everyday behavior, a largely neglected aspect of decision making is deciding which hand to use to achieve a goal. For instance, when deciding which hand to use to flip a light switch upon entering a room, the choice is influenced by many factors. These factors include what each hand is already doing (e.g, holding a phone), proximity of each hand to the switch, and future goals (e.g., desire to subsequently pick up an object with a particular hand). Our long- term goals are to elucidate the fundamental mechanisms of limb selection and movement coordination. Because limb selection is present in most behaviors, this work will provide insights broadly applicable to motor control. The posterior parietal cortex (PPC) is known to be involved in the planning and control of actions in an effector-specific manner. An emerging concept is that the same PPC regions that are involved in movement preparation and control also participate in action selection. We recently demonstrated that a parietal region known to contribute to the planning of arm movements and dubbed “the parietal reach region” (PRR), codes the spatial targets for reaches with the contralateral arm but receives information about the ipsilateral arm from the opposite hemisphere. PRR has also been implicated in the decision to reach versus saccade to a spatial target. In our first aim, we characterize limb selection behavior and determine the factors that drive limb selection. In our second aim we test the hypothesis that PRR is involved in limb selection during unimanual reaching. Next, we examine interhemispheric communication as a function of limb choice. Finally, we use reversible inactivation of the callosal fibers connecting PRR in each hemisphere to determine the role of interhemispheric competition in determining which limb to use. Collectively, these studies will have a broad impact on the field by illuminating the roles of PPC and callosal connections in a fundamental choice motor behavior. The results will lay the foundation for future studies that probe the larger bilateral frontoparietal network involved in movement control. The work may inform rehabilitation approaches for patients with neurological disorders including stroke and traumatic brain injuries in whom limb use is affected. 1 We will use the terms limb, arm, and hand interchangeably.

摘要该提案的核心目标是了解神经系统的决定使用左或右手1-这是我们日常功能至关重要的简单选择。在这里，我们专注于顶叶肢体选择的机制。尽管它是每天行为中最常见的决定之一，但决策的一个很大程度上被忽视的方面是决定使用哪种手来实现目标。例如，当决定进入房间时使用哪只手来翻转灯开关时，选择受到许多人的影响因素。这些因素包括每只手已经在做的事情（例如，握住电话），每只手的靠近要进行切换和未来的目标（例如，希望随后用特定的手捡起对象）。我们的长期术语目标是阐明肢体选择和运动协调的基本机制。由于大多数行为中都存在肢体选择，因此这项工作将提供广泛适用于马达的见解控制。已知后顶叶皮层（PPC）参与了对行动的计划和控制特定于效应器的方式。一个新兴的概念是，与运动有关的相同的PPC区域准备和控制也参与行动选择。我们最近证明了一个顶部地区已知会为手臂运动的规划做出贡献，并称为“顶距离区域”（PRR），代码与对侧臂达到的空间目标，但从相反的半球。在决定到达与空间目标。在我们的第一个目标中，我们表征肢体选择行为并确定驱动肢体的因素选择。在我们的第二个目标中，我们检验了一个假设，即PRR参与单人的肢体选择到达。接下来，我们将对肢体选择的肢体沟通检查。最后，我们使用在每个半球连接PRR的callosal纤维的可逆失活以确定的作用在确定要使用哪个肢体的情况下，声明竞争。总的来说，这些研究将有广泛的通过阐明PPC和Callosal连接在基本选择电动机中的角色来影响现场的影响行为。结果将为未来的研究奠定基础，以探测较大的双侧额叶涉及运动控制的网络。这项工作可能会为患者的康复方法提供信息神经系统疾病包括中风和肢体使用的脑损伤。 1我们将互换使用术语，手臂和手。