The Role of the Cortex in Discoordination After Stroke

皮质在中风后协调障碍中的作用

基本信息

批准号：
7569034
负责人：
JULIUS P DEWALD
金额：
$ 20.7万
依托单位：
NORTHWESTERN UNIVERSITY AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-05-20 至 2011-02-28
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Loss of independent control of joint movement in the impaired limb is a cardinal sign of stroke that is expressed in the form of stereotypic multi-joint movement patterns. Work from our laboratory has produced evidence for a loss of certain muscle coactivation patterns and associated abnormal shoulder/elbow torque coupling in the paretic arm of individuals with hemiparetic stroke. The general aim of this proposal is to elucidate the role of sensorimotor cortices in the loss of independent joint control of the paretic upper limb following stroke. We propose to study 20 individuals with chronic stroke and 20 control subjects to identify and quantify the characteristics of sensorimotor cortical activity related to the generation of isometric shoulder abduction/adduction and elbow flexion/extension torques. We hypothesize that an increased overlap of sensorimotor cortical activity is present in individuals with stroke (Aim 1). This aim will be realized using a 6 degree of freedom (DOF) load cell to provide simultaneous measurements of elbow and shoulder torques while measuring EEC from 163 scalp sites and EMG from 10 muscles in each arm. We postulate and have provided preliminary evidence for a significant overlap between cortical activity related to shoulder abduction and elbow flexion torque generation in chronic stroke subjects while not in able-bodied subjects. Subsequently, we plan to elucidate the relationship between the overlap of cortical activity and abnormal shoulder/elbow torque coupling in the paretic arm (Aim 2). We postulate that an increase in the overlap of cortical current activity is a reason for the abnormal torque coupling and serves as a predictor of the severity of discoordination in individuals with stroke. Finally, we propose to investigate the effect of a novel multidegree of freedom isometric training protocol on the overlap of cortical activity in individuals with stroke (Aim 3). Results from our recent work, using this training protocol, have shown a reduction in abnormal torque coupling between shoulder and elbow following an eight week intervention in all stroke subjects (n=7). We postulate and have provided preliminary evidence for a reduction in cortical-activity overlap in concurrence with a training-induced reduction in abnormal torque coupling. In conclusion, the combination of multichannel EEG imaging with a well controlled isometric elbow/shoulder torque generating task in subjects with chronic hemiparetic stroke is unmatched in the current literature. This study will provide new indices in the evaluation and study of discoordination as well as dynamic information on cortical plasticity in individuals with chronic hemiparetic stroke undergoing an upper extremity physical intervention. As such, the proposed study will substantially enhance our understanding of mechanisms driving discoordination in hemiparetic stroke and will provide foundations for further scientific inquiry into the development of more effective therapeutic interventions.

描述（由申请人提供）：受损肢体失去对关节运动的独立控制是中风的一个主要症状，以刻板的多关节运动模式的形式表达。我们实验室的工作提供了证据，表明偏瘫中风患者的麻痹手臂中某些肌肉共激活模式的丧失以及相关的肩/肘扭矩耦合异常。该提案的总体目的是阐明感觉运动皮层在中风后麻痹上肢独立关节控制丧失中的作用。我们计划研究 20 名慢性中风患者和 20 名对照受试者，以识别和量化与等长肩部外展/内收和肘部屈曲/伸展扭矩的产生相关的感觉运动皮层活动的特征。我们假设中风患者的感觉运动皮层活动重叠增加（目标 1）。这一目标将通过使用 6 自由度 (DOF) 称重传感器来实现，该传感器可同时测量肘部和肩部扭矩，同时测量 163 个头皮部位的 EEC 和每只手臂 10 块肌肉的 EMG。我们假设并提供了初步证据，证明慢性中风受试者中与肩部外展和肘部屈曲扭矩产生相关的皮质活动之间存在显着重叠，而在健全受试者中则不然。随后，我们计划阐明皮层活动重叠与瘫痪手臂异常肩/肘扭矩耦合之间的关系（目标2）。我们假设皮质电流活动重叠的增加是异常扭矩耦合的原因，并可作为中风个体不协调严重程度的预测因子。最后，我们建议研究一种新颖的多自由度等距训练方案对中风患者皮质活动重叠的影响（目标 3）。我们最近使用此训练方案的工作结果表明，对所有中风受试者（n = 7）进行八周干预后，肩部和肘部之间的异常扭矩耦合有所减少。我们假设并提供了初步证据，证明皮质活动重叠的减少与训练引起的异常扭矩耦合的减少同时发生。总之，在慢性偏瘫中风受试者中，多通道脑电图成像与良好控制的等长肘/肩扭矩生成任务的结合在当前文献中是无与伦比的。这项研究将为接受上肢物理干预的慢性偏瘫卒中个体的不协调性评估和研究以及皮质可塑性的动态信息提供新的指标。因此，拟议的研究将大大增强我们对偏瘫中风不协调机制的理解，并将为进一步科学探究开发更有效的治疗干预措施奠定基础。