Coordinating Movement Among Muscles and Joints

协调肌肉和关节之间的运动

• 批准号: 7061275
• 负责人: GERALD L GOTTLIEB
• 金额: $ 35.12万
• 依托单位: BOSTON UNIVERSITY (CHARLES RIVER CAMPUS)
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-06-01 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7061275
• 关键词: arm; biomechanics; central nervous system; clinical research; elbow; electromyography; gait; hand; human subject; joints; leg; limb movement; mathematical model; model design /development; muscle function; neuroregulation; psychomotor function; statistics /biometry; wrist

DESCRIPTION (provided by applicant): Because the motor control system is able to perform an almost limitless array of movements, it is usually blessed in a very broad sense with a surplus number of degrees of freedom when it is required to perform any single movement. Despite this fact, when evaluated quantitatively, human (and primate) voluntary movements display a considerable degree of kinematic consistency both within and across subjects. Over the last six years, we have discovered that there is often an equal or greater degree of consistency when movement is evaluated at the level of joint torques. We have postulated that kinematic consistency is a consequence of internal rules for the generation of joint torque patterns. When external constraints on performance are modest (as they are for many of our common movements), the CNS imposes an internal constraint. That constraint is to apply similar torque patterns at multiple joints so that, when plotted in a joint torque space, the torque trajectory lies close to a straight line, a "linear synergy." The necessary corollary of this is that if there are external constraints that are incompatible with linear synergy, the CNS must learn to use a more complex, nonlinear strategy. The research described here is intended clarify the circumstances under which linear synergy is present and when it is not. 1) We will examine if movements to targets that are made around intermediate, "via-point" targets, can be decomposed into two serial movements, each of which obeys linear synergy although the movement as a whole does not. 2) We will examine how the application of an external load alters linear synergy for movements of different directions. 3) We will explore linear synergy during gait to see if the imposition of swing-phase constraints reduces linear synergy. 4) We will explore the gait of patients with stroke to test the hypothesis that pathological movement deficits reflect either the inability to control the independent scaling of torques at different joints or the inability to break away from linear synergy when the task requires.

描述(申请人提供)：由于电机控制系统能够执行几乎无限的运动，当需要执行任何单个运动时，它通常在非常广泛的意义上具有多余的自由度。尽管如此，当进行定量评估时，人类(和灵长类)的自愿运动无论是在受试者内部还是在受试者之间都表现出相当程度的运动学一致性。在过去的六年里，我们发现，在关节扭矩水平上评估运动时，往往存在相等或更大程度的一致性。我们假设运动学一致性是关节扭矩模式生成的内部规则的结果。当对性能的外部约束是适度的(就像我们许多常见的动作一样)，中枢神经系统就会施加内部约束。这个约束是在多个关节上应用类似的扭矩模式，以便在关节扭矩空间中绘制扭矩轨迹时，扭矩轨迹接近一条直线，即“线性协同”。其必然的推论是，如果存在与线性协同不相容的外部约束，中枢神经系统必须学会使用更复杂、更非线性的策略。这里描述的研究旨在澄清线性协同作用存在和不存在的情况。1)我们将研究是否可以将中间目标周围的目标运动分解为两个连续运动，每个运动服从线性协同，尽管运动作为一个整体不服从线性协同。2)我们将研究外加载荷如何改变不同方向运动的线性协同效应。3)我们将探索步态中的线性协同，看看施加摆动阶段的限制是否会减少线性协同。4)我们将探索中风患者的步态，以检验这一假设，即病理性运动缺陷反映了无法控制不同关节扭矩的独立缩放，或者无法在任务需要时脱离线性协同。