Augmenting Neuroplasticity through Visual and Proprioceptive Feedback

描述（由申请人提供）： 在美国，中风是继心血管疾病和癌症之后的主要死亡原因，也是老年患者身体残疾的主要原因。目前中风康复的标准是强烈的物理治疗。该奖学金的总体目标是探索创新的康复技术，优化运动中心的神经元可塑性。由于视觉系统对运动系统的广泛影响，我们建议探索使用基于视觉的反馈通过Hebbian机制促进运动皮层激活的潜力。通过使用虚拟现实来改变视觉反馈，我们计划测试这样一个假设，即夸大运动和该运动的视觉反馈之间的差异会增加运动皮层的兴奋性。我们将在健康受试者和慢性中风患者中测试这一原则。如果成功，我们的数据可能不仅对慢性卒中患者而且对急性卒中阶段的患者具有重要意义，这些患者具有最大的神经可塑性潜力。我们还将测试反馈对两个半球的交叉和非交叉皮质脊髓通路的影响，以充分映射到增强视觉反馈产生的神经生理学变化的解剖位点。我们假设，夸大错误的视觉领域在手指屈曲进行健康受试者将增加经颅磁刺激（sTMS）诱导的运动诱发电位（MEP）在静止的手（相对于真实的反馈）。我们的初步数据表明，这种影响可能产生在运动皮层同侧的移动的手，可能介导的交叉皮质脊髓通路。我们将进一步测试半球间的相互作用，通过使用重复经颅磁刺激（rTMS），以减少半球间抑制（IHI）的主要运动皮层，以测试这是否会提高兴奋性的去抑制运动皮层。最后，我们将测试增强反馈是否也会增加慢性中风患者运动皮层的兴奋性。我们的初步数据表明，受损半球的运动皮层可能对这种神经可塑性变化敏感。如果成功的话，所提出的方法将铺平道路，通过选择性地支持对侧和同侧运动通路，从而最佳地重新映射皮层神经回路的中风康复的新的反馈为基础的方法的发展。建立一个强有力的基于证据的理解，了解哪些形式的中风康复治疗是真正有效的是至关重要的。通过虚拟现实改变视觉反馈可能是增强急性和慢性中风患者感觉运动系统的一种稳健方法。在整个奖学金期间，主要目标是探索这种技术，希望确定一种新的综合方法，中风康复，从而帮助治疗师在结构训练程序，为他们的病人，以促进功能恢复中风后。 公共卫生相关性： 随着美国老年人口在未来十年的激增，神经系统疾病，如中风将不幸地变得更加普遍。除了提高意识和制定中风预防计划外，我们还必须集中精力完善现有的中风康复技术。至关重要的是要建立一个强有力的基于证据的理解，哪些形式的治疗可能工作，为什么他们可能工作，以及他们可能是最有益的。

DESCRIPTION (provided by applicant): Stroke is a leading cause of death in the United States, following cardiovascular disease and cancer, and is also the leading cause of physical disability among elderly patients. The current standard in stroke rehabilitation is intense physical therapy. The overall goal of this fellowship is to explore innovative rehabilitation techniques that optimize neuronal plasticity in motor centers. Because of the extensive influence of the visual system on the motor system, we propose to explore the potential of using visually-based feedback to facilitate activation of motor cortex via Hebbian mechanisms. By using virtual reality to alter visual feedback, we plan to test the hypothesis that exaggerating a discrepancy between movement and visual feedback of that movement will increase excitability of the motor cortex. We will test this principle in healthy subjects and in patients with chronic stroke. If successful, our data may have important implications not only in chronic stroke patients but also for patients in the acute stroke phase, who have the greatest potential for neural plasticity. We will also test the effects of feedback on the crossed and uncrossed corticospinal pathways of both hemispheres to fully map anatomical loci onto the neurophysiological changes produced by augmented visual feedback. We hypothesize that exaggerating error in the visual domain during finger flexion performed by healthy subjects will increase transcranial magnetic stimulation (sTMS)-induced motor evoked potentials (MEPs) in the stationary hand (relative to veridical feedback). Our preliminary data suggest that this effect may be produced in the motor cortex ipsilateral to the moving hand, potentially mediated by crossed corticospinal pathways. We will further test interhemispheric interactions by using repetitive transcranial magnetic stimulation (rTMS) to diminish interhemispheric inhibition (IHI) of the primary motor cortex to test if this will enhance the excitability of the disinhibited motor cortex. Last, we will test if augmented feedback will also increase the excitability of motor cortex in chronic stroke patients. Our preliminary data suggest that the motor cortex of the lesioned hemisphere may be susceptible to such neuroplastic changes. If successful, the proposed approach will pave the way for development of novel feedback-based approaches in stroke rehabilitation by selectively bolstering contralateral and ipsilateral motor pathways, thus optimally remapping cortical neural circuits. It is vital to establish a strong evidence-based understanding of which forms of stroke rehabilitation therapy are truly effective. Altering visual feedback via virtual reality may be a robust way of augmenting the sensorimotor system of acute and chronic stroke patients. Throughout this fellowship period, the primary objective is to explore this technique in hopes of determining a novel comprehensive approach to stroke rehabilitation, thus aiding therapists in structuring training routines for their patients to facilitate functional recovery following stroke. PUBLIC HEALTH RELEVANCE: As the elderly population in the United States skyrockets throughout the next decade, neurological disorders such as stroke will unfortunately become more prevalent. In addition to increasing awareness and instituting stroke prevention programs, we must also focus our efforts on perfecting current stroke rehabilitation techniques. It is vital to establish a strong evidence-based understanding of which forms of therapy may work, why they may work, and for whom they may be most beneficial.