Functional role and Modulation Of Brain Plasticity In He

我们活动的目标是了解人类中枢神经系统中可塑性变化的功能作用和底物，并开发新的治疗方法来恢复中风后的功能。我们的大部分工作集中在研究正常志愿者和中风患者的人体运动、体感和视觉系统的可塑性变化。今年，我们发现触觉辨别技能的行为收益一方面与去传入有关，另一方面与去传入有关。关于运动皮质中的使用依赖性可塑性，我们发现，通过TMS刺激和TDCs刺激相邻身体部分表征，可以调节一个身体部位表征的可塑性。我们还开发了两种策略来增强使用依赖的可塑性：通过给药和同时给予经颅磁刺激。我们发现，TDC形式的非侵入性脑刺激可以促进中风后的神经康复努力。一项评估非侵入性脑机接口在控制中风后手运动的应用的项目正在进行中。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质)参与卒中后运动功能恢复的认识有了进展。有证据表明，theta猝发刺激(TBS)，特别是与多巴胺能药物联合使用，已显示出对人类运动皮质兴奋性的影响，表明它可能增强突触的可塑性，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显示出在卒中后产生临床收益的前景，我们今年开始了一项新的研究来解决这一假说。我们有兴趣研究的另一项技术是，是否可以通过将外周高频刺激(PHFS)和tDCs(PHFS+tDCs)联合应用于受影响大脑半球的躯体感觉皮质，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利影响。这种方法可能确定新的策略来促进中风后的功能恢复，并可能提供对这些行为收益所涉及的机制的更深层次的了解。在这种认识的基础上，我们开始设计和测试干预措施，以改善中枢神经系统损伤后的运动障碍。

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.