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底物，并开发新的治疗方法来恢复功能。我们的大部分工作集中在研究人类运动、体感和视觉系统的可塑性变化。今年，我们发现一只手的触觉辨别技能的行为变化与另一只手的神经分化有关。在视觉领域，我们发现光剥夺与视觉皮层兴奋性的增加和该区域GABA水平的降低有关。这一发现证明了利用磁共振波谱技术在线监测行为人类大脑皮层GABA每分钟变化的可能性。关于运动皮层的使用依赖性可塑性，我们发现可以通过刺激经颅磁刺激和刺激邻近的身体部位表征来调节一个身体部位表征的可塑性。我们还制定了两种策略来增强使用依赖的可塑性：通过服用d-安非他明和同时服用经颅磁刺激。在与德国研究人员的合作中，我们发现幻肢痛患者的躯体感觉和运动皮层的表征可塑性比无疼痛截肢者更突出。在慢性脑卒中后的康复领域，我们发现一种名为“约束诱导疗法”的康复治疗似乎可以提高脑卒中后长时间瘫臂的使用量。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。我们未来的目标是提高我们对人类功能可塑性的功能作用和基础的理解。在这种理解的基础上，我们开始设计和测试干预措施，以改善人类疾病后的运动障碍。

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. Most of our work has focused on the study of plastic changes in the human motor, somatosensory and visual systems. This year, we identified behavioralgains in tactile discriminative skills in one hand associated with deafferentation in the other hand. In the visual domain, we found that light deprivation is associated with an increase in excitability of the visual cortex and a decrease in GABA levels in that region. This finding demonstrates the possibility of online monitoring minute to minute of changes in cortical GABA in behaving humans using magnetic resonance spectroscopy. 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. We also developed two strategies to enhance use-dependent plasticity: by administration of d-amphetamine and also by concomitant administration of transacranial magnetic stimulation. In a collaborative effort with German investigators, we found that representational plasticity in somatosensory and motor cortex is more prominent in patients with phantom limb pain than in amputees without pain. In the area of rehabilitation after chronic stroke, we found that a rehabilitation treatment called "constraint induced therapy" appears to enhance the amount of use of the paretic arm long time 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. Our future goals are to improve our understanding of the functional role and substrates underlying plasticity of function in humans. On the basis of this understanding, we are starting to design and test interventions to improve motor disability after human diseases.