Motor Control of Human Arm Stiffness

描述(申请人提供)：这项工作的重点是神经系统如何控制人类手臂僵硬-对强加的位移的抵抗力。长期目标是了解僵硬控制如何整合到运动的持续控制中，以及如何在与环境的交互中以自适应的方式使用它。所有提出的研究都与理解刚度的自愿控制这一共同目标有关。这些研究从评估僵硬控制的基本属性，扩展到研究僵硬控制如何更普遍地参与动作的产生，以及评估僵硬如何用于与环境的相互作用。在整个过程中都采用了一个共同的程序-使用机器人操作器来向ARM提供精确的机械扰动。本研究将(1)记录刚度控制的基本性质。它将确定僵硬控制的参照系，评估僵硬学习的持久性，并评估中心和反射对僵硬的贡献的平衡。(2)本工作将表征运动中手臂僵硬控制的特性。它将评估僵硬和运动速度之间的关系，评估僵硬控制在不同轨迹要求和最终精度的运动产生中的作用。它还将建立在静态条件下测量的刚性和在自由运动时的刚性之间的关系(3)这些研究还将建立在与环境相互作用期间的刚性控制特性。他们将评估在与具有不同惯性属性的对象交互时修改刚度的方式，并确定当力施加到具有不同表面属性的对象时，对刚度模式进行不同修改的程度。

DESCRIPTION (provided by applicant): This work focuses on how the nervous system controls human arm stiffness-the resistance to imposed displacements. The long-term goal is to understand how stiffness control is integrated into the ongoing control of movement and how it is used in an adaptive fashion during interactions with the environment. All of the proposed research is related by the common aim of understanding the voluntary control of stiffness. The studies extend from an assessment of basic properties of stiffness control, to studies that examine how stiffness control is more generally involved in the production of movements and to studies that assess how stiffness is used in interactions with the environment. A common procedure is adopted throughout-the use of a robotic manipulator to deliver precise mechanical perturbations to arm. The research will (1) document the basic properties of stiffness control. It will identify the frame of reference for stiffness control, evaluate the durability of stiffness learning, and assess the balance of central and reflex contributions to stiffness (2) The work will characterize the properties of arm stiffness control during movement. It will assess the relationship between stiffness and movement speed, evaluate the role of stiffness control in the production of movements that differ in terms of trajectory requirements and final accuracy. It will also establish the relationship between stiffness as measured under static conditions and stiffness during voluntary movement (3) The studies will also establish properties of stiffness control during interactions with the environment. They will assess the ways in which stiffness is modified when interacting with objects that have different inertial properties and determine the extent to which patterns of stiffness are differentially modified when forces are applied to objects with different surface properties.