Functional role and Modulation Of Brain Plasticity In He

我们的目标是了解人类中枢神经系统可塑性变化的功能作用和基础，并开发中风后功能恢复的新治疗方法。我们的大部分工作都集中在研究人类运动、体感和视觉系统在正常志愿者和中风患者中的可塑性变化。今年，我们发现一只手的触觉辨别技能的行为增益与另一只手的神经分化有关。关于运动皮层的使用依赖性可塑性，我们发现通过TMS刺激和tDCS刺激相邻身体部位表征来调节一个身体部位表征的可塑性是可能的。我们还开发了两种策略来增强使用依赖的可塑性：通过药理学药物的管理，也通过同时管理经颅磁刺激。我们发现，tDCS形式的无创脑刺激有助于中风后的神经康复。一个项目正在评估非侵入性脑机接口在中风后控制手部运动的应用。我们对完整的大脑半球和非初级运动区（特别是背侧运动前皮层）在中风后运动功能恢复中的作用有了更深入的了解。有证据表明，theta burst刺激（TBS），特别是与多巴胺能药物联合使用，对人类运动皮层的兴奋性有影响，表明它可能增强突触可塑性，改善健康人的运动训练。考虑到多巴胺能调节和TBS之间的协同作用可能会在中风后产生临床收益，我们今年开始了一项新的研究来解决这一假设。我们感兴趣的另一项技术是，我们是否可以通过将外周高频刺激（pHFS）与tDCS （pHFS+tDCS）联合应用于受影响半球的体感觉皮层，来增强外周高频刺激（pHFS）对慢性中风患者内隐触觉和触觉学习的有益影响。这种方法可能会确定新的策略来增强中风后的功能恢复，并可能为这些行为收益的机制提供更深入的见解。基于这种理解，我们开始设计和测试干预措施，以改善中枢神经系统病变后的运动障碍。

The goal of our activity is to understand the functional role and substrates underlying plastic changes in the human central nervous system and develop novel therapeutic approaches for recovery of function following stroke. Most of our work has focused on the study of plastic changes in the human motor, somatosensory and visual systems in normal volunteers and patients with stroke. This year, we identified behavioral gains in tactile discriminative skills in one hand associated with deafferentation in the other hand. In relation to use- dependent plasticity in motor cortex, we discovered that it is possible to modulate plasticity in one body part representation by stimulation with TMS and by stimulation of adjacent body part representations by tDCS. We also developed two strategies to enhance use-dependent plasticity: by administration of pharmacological agents and also by concomitant administration of transcranial magnetic stimulation. We discovered that noninvasive brain stimulation in the form of tDCS can contribute to neurorehabilitative efforts after stroke. A project is under way to evaluate application of noninvasive brain-computer interface to control hand motions after stroke. We have advanced in the understanding of the involvement of the intact hemisphere and nonprimary motor areas (particularly dorsal premotor cortex) in recovery of motor function after stroke. Evidence suggests that theta burst stimulation (TBS), especially combined with dopaminergic agents has shown effects on the excitability of human motor cortex, suggesting it may enhance synaptic plasticity and improve motor training in healthy humans. Considering that synergy between dopaminergic modulation and TBS may show promise to produce clinical gains after stroke, we have begun a new study this year to address this hypothesis. One other techniques we are interested in investigating is whether we can enhance beneficial effects of peripheral high-frequency stimulation, (pHFS), on implicit tactile and haptic learning in chronic stroke patients by a combined application of pHFS with tDCS (pHFS+tDCS) applied to the somatosensory cortex of the affected hemisphere. This approach might identify novel strategies to enhance the functional recovery after stroke and might provide deeper insight into the mechanisms involved in these behavioral gains. On the basis of this understanding, we are starting to design and test interventions to improve motor disability after lesions in the central nervous system.