Planning and Updating in Frontoparietal Networks for Grasping

脑损伤后出现的一些行为后遗症，如中风或创伤性损伤， 可以用感觉信息和运动指令的整合异常来解释。这个项目 使用脑成像和非侵入性脑刺激，结合新颖的抓握扰动， 运动与机器人和虚拟环境，以研究额顶叶脑区在 感觉运动整合的不同阶段，并确定大脑网络的具体贡献， 目标导向的抓取该项目的总体目标是使用健康人体病变模型， 关于额顶皮层在感觉运动的两个主要阶段中所起作用的因果推论 整合：在运动规划期间，当目标的视觉信息和手的触觉信息 被转换成运动指令，并且在运动更新期间， 发生运动指令的结果（生成前向模型）。我们利用久经考验的 涉及对目标和手臂电机设备的扰动的方法（外部和外部的扰动）， 内在空间），已被用来研究感觉运动的整合，在达到系统，并将其应用到 研究抓取电路，它是由一个独特的和隔离的神经网络控制， 替补演员这是第一个系统的研究，在人类测试的独特贡献额顶叶 大脑皮层在规划和正向建模的手形抓，以及这些过程如何相互作用， 内在与外在参照系的背景。目标1的中心目标是使用功能性磁性材料， 磁共振成像（fMRI），以确定在外部与内部空间的运动规划的神经基础， 相应地测试这些区域与fMRI神经导航引起的短暂病变的因果关系 进行磁刺激目标2通过测试因果关系来补充前面的目标 额顶叶区的变化。在这里，我们利用多变量分析， 在抓取过程中对手部结构和运动目标的新扰动的运动学响应， 分离这些区域参与手形与整合的前向模型的生成 感官信息进入运动计划。 公共卫生相关性：该项目将促进我们对神经系统疾病的基本神经机制的理解。 抓握，这是人类神经科学中研究不足的领域。它与公共卫生密切相关，因为 这些发现将为感觉运动整合的神经基础提供信息，解释一系列的病理学， 运动和感知，并帮助识别皮质目标的干预提取神经信号， 脑机接口和皮层刺激在患者人群中的应用。

A number of the behavioral sequelae that occur after damage to the brain, such as stroke or traumatic injury, can be explained by abnormalities in the integration of sensory information and motor commands. This project uses brain imaging and non-invasive brain stimulation, combined with novel perturbations of grasping movements with robotics and virtual environments to study the roles played by frontoparietal brain areas in different stages of sensorimotor integration and to identify specific contributions of brain networks subserving goal-directed grasping. The overarching goal of this project is use a healthy-human lesion model to make causal inferences regarding the roles played by frontoparietal cortices in two major stages of sensorimotor integration: during motor planning when visual information of the target goal and haptic information of the hand is transformed into motor commands, and during movement updating when estimates of the sensory consequences of motor commands occur (generation of a forward model). We leverage the time-tested approaches involving perturbations to the target goal and the arm motor plant (perturbations of extrinsic and intrinsic space) that have been used to study sensorimotor integration in the reach system, and apply them to study the grasp circuit, which is controlled by a unique and segregated neural network that is comparatively understudied. This is the first systematic study in humans to test the unique contributions of frontoparietal cortices in planning and forward modeling of hand shape for grasping, and how these processes interact in the context of intrinsic versus extrinsic reference frames. The central goal of Aim 1 is to use functional magnetic resonance imaging (fMRI) to identify the neural bases of motor planning in external vs. internal space and accordingly test the causal involvement of these regions with fMRI-neuronavigated transient lesions elicited with transcranial magnetic stimulation. Aim 2 complements the previous aim by testing the causal involvement of grasp-related frontoparietal areas in online updating of grasp. Here, we leverage multivariate analyses of kinematic responses to novel perturbations of hand configuration and movement goals during grasping to dissociate the involvement of these areas in generation of forward models for hand shape versus integrating sensory information into the motor plan. PUBLIC HEALTH RELEVANCE: This project will advance our understanding of basic neural mechanisms of grasping, a largely understudied area of human neuroscience. It is highly relevant to public health because these findings will inform the neural underpinnings of sensorimotor integration, explain a host of pathologies of movement and perception, and aide in identifying cortical targets for interventions extracting neural signals for brain-computer interfaces and cortical stimulation in patient populations.