Augmentation of Locomotor Adaptation Post-Stroke

描述 我的最终目标是在理解人类运动机制的基础上开发治疗方法，以及如何利用这种理解以最有效的方式重新训练行走。一个基本的了解运动功能障碍的具体机制，需要制定个性化的康复计划，以改善行走性能。 如果详细了解这些机械基础和对康复的反应之间的关系，治疗师将改善临床决策，使他们能够针对运动功能障碍的特定神经机械贡献者。此外，了解神经功能障碍患者如何适应训练任务将有助于优化治疗方案，其主要目的是促进长期学习。该应用反映了基于个体的、理论驱动的干预的目标，其通过针对行走的特定生物力学元素、测定运动学习以及应用连续性非侵入性电刺激来减少神经激活损伤。拟议的工作将继续我的训练，在运动控制和学习下，我目前的CDA-1导师博士史蒂芬考茨。一个令人兴奋的新元素，将被纳入拟议的工作是电刺激大脑作为一种干预，以潜在地提高运动适应和运动学习潜力。我将在导师马克乔治博士的指导下获得这项新技能，他是脑刺激的世界领导者，也是拉尔夫H。约翰逊退伍军人医疗中心。建议的项目旨在确定训练特定运动适应的有效策略，建立激活中风后运动神经回路的最佳电极配置，并 通过连续性非侵入性脑刺激改善适应性。在接下来的五年里，我们建议专注于三个具体目标：1）发展与应用经颅直流电刺激（tDCS）进行中风后运动恢复相关的技能; 2）进步运动适应评估技能; 3）进行基础研究，为随后的优异奖做好准备。对于目标1，我们将招募40名慢性卒中患者（卒中后超过6个月），以确定tDCS的最佳配置，以引起卒中后轻偏瘫患者的立即下肢肌肉激活。最近的tDCS在中风后上肢的调查表明，同病灶的兴奋和对病灶的抑制都是有效的，在增加运动控制，但我们假设，这两个位置的组合将产生最大的改善下肢运动激活和运动任务所需的肢体间协调。对于目标2，我们将招募40名慢性卒中患者，以区分两种方法（跑步机倾斜行走和COM辅助行走），用于对卒中后出现推进缺陷的患者进行质心加速度（COMa）再训练。为此，我们假设跑步机倾斜行走将证明COMa曲线的正常化，增加的麻痹推进，和改善的COMa曲线的平滑度（谐波比）> COM辅助行走>比单独在跑步机上行走。最后，对于目标3，我们将从目标2中招募相同的40名个体，以确定tDCS与COMa训练相结合的效果。我们假设，使用最佳电极配置（目标1中确定）和最佳COMa训练方法（目标2中根据个体评估确定）进行的训练将优于使用假刺激进行的COMa训练。此外，我们假设，多天的训练将增加皮层兴奋性，并证明改善修改的COMA。这项工作不仅将产生重要的贡献，有关运动学习的文献具体到运动，但也将提供必要的信息，提出一个优异奖在职业发展期结束。

DESCRIPTION My ultimate goal is to develop therapies based on an understanding of the mechanisms of human movement and how that understanding can be utilized to re-train walking in the most effective manner possible. A fundamental understanding of the specific mechanisms underlying locomotor dysfunction is required for developing individualized rehabilitation programs targeting improved walking performance. Therapists will improve clinical decision-making if detailed knowledge of the relationship between these mechanistic underpinnings and response to rehabilitation allows them to target specific neuromechanical contributors to motor dysfunction. Furthermore, knowledge of how individuals with neurological impairments adapt to training tasks will assist in the optimization of treatment programs, which essentially aim to promote long-term learning. This application reflects the goal of indivually-based, theory-driven interventions by targeting specific biomechanical elements of walking, assaying motor learning, and applying adjunctive non-invasive electrical stimulation to decrease neural activation impairments. The proposed work will continue my training in motor control and learning under my current CDA-1 mentor Dr. Steven Kautz. An exciting new element that will be incorporated into the proposed work is electrical stimulation of the brain as an intervention to potentially improve motor adaptations and motor learning potential. I will attain this new skill under the direction of mentor Dr. Mark George, a world leader in brain stimulation and a physician investigator at the Ralph H. Johnson VA Medical Center. The proposed project seeks to identify effective strategies for training a specific locomotor adaptation, to establish the optimal configuration of electrodes to activate neural circuits involved in post-stroke locomotion, and to improve adaptations via adjunctive non- invasive brain stimulation. Over the next five years, we propose to focus on three specific goals: 1) develop skills associated with applying transcranial direct current stimulation (tDCS) for locomotor recovery post-stroke; 2) progress motor adaptation assessment skills; and 3) perform a foundational research study that prepares investigator for subsequent Merit Award. For Goal 1, we will recruit 40 individuals with chronic stroke (greater than six months post-stroke) in order to determine the optimal configuration of tDCS to elicit immediate lower extremity muscle activation in those with post-stroke hemiparesis. Recent investigations of tDCS in the upper extremity post-stroke indicate that ipsilesional excitation and contralesional inhibition are both effective at increasing motor control, but we hypothesize that a combination of the two placements will produce the largest improvements in lower extremity motor activation and interlimb coordination required for a locomotor task. For Goal 2, we will recruit 40 individuals with chronic stroke to distinguish between two approaches (treadmill incline walking and COM-assisted walking) for retraining the center of mass acceleration (COMa) in those post-stroke presenting with propulsion deficits. For this goal, we hypothesize that treadmill incline walking will demonstrate normalization of the COMa curve, increased paretic propulsion, and improved smoothness of the COMa curve (harmonic ratio) > COM-assisted walking > than walking on a treadmill alone. Lastly, for Goal 3 we will enroll the same 40 individuals from Goal 2 to determine the effect of combining tDCS with COMa training. We hypothesize that training with the optimal electrode configuration (determined in Aim 1) and the optimal method for training COMa (determined from individual assessments in Aim 2) will be superior to training COMa with sham stimulation. Furthermore, we hypothesize that multiple days of training will increase cortical excitability and demonstrate improved modification of the COMa. This work will not only yield important contributions to the literature regarding motor learning specific to locomotion, but also will provide the necessary information to propose a Merit Award at the end of the Career Development period.