Enhancement of hand motor function after cervical spinal cord injury

描述(由申请人提供)： 手运动功能障碍是退伍军人颈髓损伤(SCI)的主要缺陷。虽然康复干预在改善手运动功能方面取得了成功，但总体效果仍然有限。本研究的目的是研究颈椎脊髓损伤后促进手运动控制的中枢神经系统通路的生理学，并通过非侵入性脑刺激和运动训练促进手运动的恢复。我们关注与手部运动功能相关的两个基本方面：精确的握力和手腕的屈伸。这些是我们大多数日常生活活动所必需的技能；因此，我们的结果可能通过以下方式直接影响退伍军人及其照顾者的生活质量 提高他们的独立性和关爱水平。我们将研究运动皮质和脊髓运动神经元在颈椎脊髓损伤后参与精确握力和腕部运动的肌肉控制中的作用(目标1)。经颅磁刺激(TMS)将被用来研究针对手指和腕部肌肉的皮质脊髓和皮质内通路的传递，而周围神经刺激将被用来评估手指和腕部运动神经元的兴奋性。这些研究将确定脊髓损伤对控制手运动的中枢神经系统通路的影响。然后，我们建议通过使用高频无创重复TMS(RTMS)和运动训练(目标2)的新方案来促进手运动功能的恢复。首先，rTMS将以一种依赖于任务的方式在精确握力和手腕运动中使用，以诱导皮质可塑性并增强手部肌肉的自愿输出。其次，rTMS将在涉及精确握力和手腕运动的视觉运动训练任务中以依赖于任务的方式应用。这些独特的方法旨在促进功能相关的手运动中的神经可塑性，这是以前从未做过的。拟议中的研究将基础科学人类研究和翻译神经科学紧密结合在一起。无创脑刺激的新方法可能为脊髓损伤后手运动功能的恢复开辟新的方向。对于患有颈椎脊髓损伤的退伍军人来说，缺乏被广泛接受的手运动障碍的治疗方法，以及目前干预措施的有限行为收益，突显了这些调查的重要性。

DESCRIPTION (provided by applicant): Impairment in hand motor function is a major deficit in veterans with cervical spinal cord injury (SCI). While rehabilitative interventions have shown success in improving aspects of hand motor function their overall effects remain limited. The goals of this proposal are to examine the physiology of CNS pathways contributing to the control of hand movements after cervical SCI, and to promote the recovery of hand movements by using non-invasive brain stimulation and motor training. We focus on two basic aspects involved in hand motor function: a precision grip and wrist flexion and extension. These are necessary skills for most of our daily-life activities; therefore, our results may directly impact the quality of life for veterans and their caregivers by enhancing their independence and level of care. We will investigate the contribution of the motor cortex and spinal motoneurons to the control of muscles involved in precision grip and wrist movements after cervical SCI (Aim 1). Transcranial magnetic stimulation (TMS) will be used to examine transmission in corticospinal and intracortical pathways targeting finger and wrist muscles, whereas peripheral nerve stimulation will be used to assess the excitability of finger and wrist motoneurons. These studies will identify the effects of SCI on CNS pathways controlling hand movements. Then, we propose to enhance the recovery of hand motor function by using novel protocols of high frequency non-invasive repetitive TMS (rTMS) and motor training (Aim 2). First, rTMS will be used during precision grip and wrist movements in a task- dependent manner to induce cortical plasticity and enhance voluntary output of hand muscles. Second, rTMS will be applied in a task-dependent manner during a visuo-motor training task that involves precision grip and wrist movements. These unique approaches aim at promoting neuroplasticity during functionally relevant hand movements, which has not been done before. The proposed studies tightly couple basic scientific human research and translational neuroscience. The novel approaches of non-invasive brain stimulation may open new directions for restoring hand motor function after SCI. The absence of well-accepted treatments for hand motor impairments for veterans with cervical SCI and the limited behavioral gains of present interventions underline the importance of these investigations.