Multi-Joint Sensorimotor Dysfunction of the Stroke Arm

这项研究合作的目的是研究使用传感器反馈来增强中风后手臂运动控制的功能含义。我们将研究手臂运动控制的两个关键功能方面：1)伸展，涉及肩膀和肘部肌肉组织的协调行动；2)抓握，包括手指位置和力的控制。对于每个系统，我们将证明来自非同源关节的感觉反馈对运动控制有重要影响。首先，我们将研究腕部/手部感觉反馈对肘部和肩部肌肉组织的腹内反射耦合，反之亦然。在本研究的目的1中，我们将展示手肘和手指的机动拉伸在未受干扰的肌肉中产生反射活动。这些影响将比较中风后和神经完整的个体使用肌腱拍打扰动。由姿势、电刺激、振动和麻醉组成的感觉操作将用于改变异位反射反应。在展示了跨关节的反射耦合之后，我们将检查这种反射耦合可能对运动功能的影响。在Aim 2中，上臂的运动控制任务（例如伸手）将在手指和手腕的感觉操作中进行测试。同样，手的运动任务将通过改变肘部和肩部的感觉输入来测试。这些研究将证明来自非同源关节的感觉信号可以显著增强运动功能。本研究结果将为脑卒中后手臂功能的康复提供一种新的途径。我们假设，通过开发提供人工感官反馈的新技术，可以实现手臂功能的实质性改进。此外，使用本研究将证明的原理，传统疗法可能会更有效地应用。

The purpose of this research partnership is to investigate the functional implications of using sensor feedback to enhance motor control of the arm post-stroke. Two key functional aspects of motor control of the arm will be examined: 1) Reach, which involves coordinated actions of the shoulder and elbow musculature and 2) grasp, which incorporates both finger position and force controls. For each system, we will demonstrate that sensory feedback from nonhomologous joints has a significant effect on motor control. Initially, we will examine the intralimb reflex coupling of wrist/hand sensory feedback on elbow and shoulder musculature and visa versa. For Aim 1 of this study, we will show that motorized stretch of the elbow and fingers produces reflex activity in muscles that are not perturbed. These effects will be compared between post-stroke and neurologically intact individuals using tendon tap perturbations. Sensory manipulations consisting of posture electrical stimulation, vibration and anesthesia will be used to modify the heteronymous reflex responses. Having demonstrated reflex coupling across joints, we will then examine the effects that this reflex coupling may have on motor function. In Aim 2, motor control tasks of the upper arm (e.g. reach) will be tested during sensory manipulations of the fingers and wrist. Similarly, motor tasks of the hand will be tested with modifications of sensory inputs to the elbow and shoulder. These studies will demonstrate that sensory signals from nonhomologous joints can substantialy enhance motor function. The results of this study will suggest a new type of approach for rehabilitation of arm function post-stroke. We postulate that substantial improvements in arm function can be achieved by developing new technologies that provide artificial sensory feedback. In addition, conventional therapies may be applied more efficiently or effectively using the principles that will be demonstrated by this study.