Sensorimotor Control of Human Jaw Movement

本提案描述了对人类面部运动控制的研究，主要集中在下颚。目标是了解神经信号与口面部生物力学相互作用的方式，以确定说话时的运动结果。所有提出的研究都是为了理解运动的神经和生物力学决定因素之间的关系。研究范围从颌骨的生物力学特性及其与言语变异性的关系延伸到控制信号补偿机械装置动态的程度。在整个过程中采用了一种常见的程序-使用伺服控制的机器人机械手来提供精确的机械扰动到颌骨。该研究将(1)记录颌骨的生物力学特性，特别是静态颌骨刚度与元音产生过程中的运动学变化之间的关系。(2)这项工作将描述运动过程中的颚刚度，评估刚度对运动速度的依赖，评估说话和咀嚼时的刚度，并确定运动过程中的刚度与运动可变性的时变模式之间的关系。(3)研究还将评估神经系统编码的信息的复杂性，这些信息涉及面部运动规划中的生物力学外围和外部负载。

This proposal describes studies of the control of human orofacial movement that focus on the jaw. The goal is to understand the ways in which neural signals interact with orofacial biomechanics to determine movement outcomes in speech. All of the proposed research is related by the common aim of understanding the relationship between neural and biomechanical determinants of movements. The studies extend from the jaw's biomechanical properties and their relation to speech variability to the degree to which control signals compensate for the dynamics of the mechanical apparatus. A common procedure is adopted throughout - the use of a servo-controlled robotic manipulator to deliver precise mechanical perturbations to the jaw. The research will (1) document the jaw's biomechanical properties and in particular the relationship between jaw stiffness in statics and kinematic variability during vowel production. (2) The work will characterize jaw stiffness during movement and assess the dependence of stiffness on movement speed, evaluate stiffness in speech versus mastication, and determine the relationship between stiffness over the course of movement and time-varying patterns of kinematic variability. (3) The studies will also assess the complexity of the information that the nervous system encodes concerning the biomechanical periphery and external loads in orofacial motion planning.