Acquisition and Retention of Locomotor Adaptations after Stroke

中风后运动适应的获得和保留

• 批准号: 8094408
• 负责人: Susanne M Morton
• 金额: $ 17.46万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8094408
• 关键词: Adult; Affect; Age; Behavior; Brain; Cerebellum; Chronic; Corticospinal Tracts; Development; Disinhibition; Effectiveness; Electromyography; Foundations; Frequencies; Gait; Gender; Handedness; Human; Individual; Intervention; Lead; Learning; Leg; Lesion; Limb structure; Location; Locomotor adaptation; Measures; Motion; Motor; Motor Cortex; Motor output; Movement; Output; Patients; Pattern; Phase; Physiologic pulse; Play; Process; Rehabilitation therapy; Research; Role; Side; Source; Stroke; Structure; Subgroup; System; Testing; Time; Transcranial magnetic stimulation; Walking; Work; base; chronic stroke; design; disability; improved; insight; limb movement; motor deficit; motor impairment; motor learning; nervous system disorder; novel; patient population; prevent; public health relevance; repetitive transcranial magnetic stimulation; success; visual feedback; visual motor

DESCRIPTION (provided by applicant): Motor learning forms a foundation for rehabilitation interventions to treat patients with debilitating neurological disorders such as stroke. It is now known that the cerebellum is required for motor adaptations and motor learning. The motor cortex is also involved in motor learning, but its specific role is less clear. Recent studies indicate that the motor cortex may be more involved in the consolidation and/or retention phases of motor learning than in the initial acquisition. It is not known whether individuals with stroke involving the motor cortex have deficits in retention of newly acquired motor adaptations. Broadly, the purpose of this research is to determine the effects of unilateral stroke involving the primary motor output system on retention of a newly learned visuomotor walking adaptation in humans. Motion capture, electromyography and transcranial magnetic stimulation (TMS) will be used to record limb movements and to measure and modulate corticospinal excitability, respectively. In Aim 1, visual feedback during walking will be altered to induce a novel gait pattern in healthy and stroke-affected adults that, in stroke subjects, is designed to improve symmetry of single limb support durations between the legs. Initial adaptation and retention of the new walking pattern will be measured and compared across groups at several time periods. Subject with stroke are expected to show reduced retention but relatively intact adaptation. In Aim 2, low frequency inhibitory repetitive TMS (rTMS) will be applied over the primary motor cortex (M1) of the non- lesioned hemisphere in individuals with stroke prior to walking. Effects of rTMS on the acquisition and retention of the visuomotor walking adaptation will be measured and compared to a group of stroke subjects receiving sham stimulation. Single pulse TMS will be used to measure changes in corticospinal excitability before and after rTMS. We predict that inhibitory rTMS to the non-lesioned M1 will improve retention of the walking adaptation in stroke subjects, and will be associated with disinhibition of the lesioned M1. We also expect to find that the level of benefit from rTMS varies with lesion location. Results from the proposed aims will help determine whether individuals with stroke involving the primary motor output system have deficits in acquisition and/or retention of newly adapted walking patterns and whether this deficit can be temporarily improved using rTMS. This work is particularly important because 1) it will help determine the role of the motor cortex in acquisition and/or retention of motor adaptations, 2) it will support or refute the proposed mechanism of overly strong transcallosal inhibition from the non-lesioned hemisphere as a source of motor impairment in patients with stroke, and 3) it may lead to the development of novel therapies to enhance motor learning and retention in patients with motor disability due to stroke. PUBLIC HEALTH RELEVANCE: Results from these studies will provide novel insights into brain mechanisms of impaired motor learning following stroke. Importantly, findings are expected to help lead to the development of new rehabilitation interventions to enhance motor learning of locomotor patterns in patients with stroke. Thus, this work will have broad impact on public heath, as stroke is a leading cause of long-term disability and leaves many of its victims unable to walk without assistance.

描述（由申请人提供）：运动学习形成了康复干预的基础，用于治疗患有衰弱性神经系统疾病（如中风）的患者。现在我们知道，小脑是运动适应和运动学习所必需的。运动皮层也参与运动学习，但其具体作用尚不清楚。最近的研究表明，运动皮层可能更多地参与巩固和/或保留阶段的运动学习比在初始收购。目前尚不清楚涉及运动皮层的中风患者是否在保持新获得的运动适应方面存在缺陷。概括地说，本研究的目的是确定涉及主要运动输出系统的单侧中风对人类新学习的视觉行走适应的保留的影响。运动捕捉、肌电图和经颅磁刺激（TMS）将分别用于记录肢体运动以及测量和调节皮质脊髓兴奋性。在目标1中，将改变行走过程中的视觉反馈，以诱导健康和中风患者的新型步态模式，在中风受试者中，旨在改善腿部之间单肢支撑持续时间的对称性。将在几个时间段测量和比较各组对新行走模式的初始适应和保持。中风受试者预期表现出减少的保留，但相对完整的适应。在目标2中，将在行走前对中风个体的非病变半球的初级运动皮层（M1）应用低频抑制性重复TMS（rTMS）。将测量rTMS对视觉行走适应的获得和保持的影响，并与接受假刺激的一组卒中受试者进行比较。单脉冲TMS将用于测量rTMS前后皮质脊髓兴奋性的变化。我们预测，抑制rTMS的非病变的M1将改善中风受试者的步行适应的保留，并将与去抑制的病变的M1。我们还希望发现，从rTMS受益的水平因病变部位而异。所提出的目标的结果将有助于确定涉及主要运动输出系统的中风患者是否在获取和/或保留新适应的行走模式方面存在缺陷，以及这种缺陷是否可以使用rTMS暂时改善。这项工作特别重要，因为1）它将有助于确定运动皮层在获得和/或保持运动适应中的作用，2）它将支持或反驳所提出的非损伤半球过度强烈的经胼胝体抑制机制作为中风患者运动障碍的来源，以及3）它可能导致新疗法的开发，以增强中风所致运动障碍患者的运动学习和保持。 公共卫生相关性：这些研究的结果将为卒中后运动学习受损的大脑机制提供新的见解。重要的是，研究结果有望有助于开发新的康复干预措施，以增强中风患者运动模式的运动学习。因此，这项工作将对公众健康产生广泛影响，因为中风是导致长期残疾的主要原因，许多中风患者在没有帮助的情况下无法行走。