FINGER VS ELBOW TRACKING: COMPETITION FOR CORTICAL REPRESENTATIONS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 脑中的神经可塑性变化包括持久的重组（Boroojerdi等人，2001）归因于皮层的动态电路（Sanes和Donoghue，2000）。涉及具有神经损伤，特别是中风的个体的康复研究更加强调促进大脑中的这种变化的训练范例（Carey等人，2002; Carey等人，2004; Gow等人，2004; Koski等人，2004; Liepert等人，2000年）。然而，对恢复后的重组机制的理解还远远没有完成。 复杂的技能获得或技能再学习可以促进运动皮层水平的神经可塑性表征变化，通常被称为“学习依赖性假说”（Kleim et al.，1998; Plautz等人，2000年）。Plautz等人（2000年）通过分别训练松鼠猴进行复杂的小孔颗粒回收任务或简单的大孔颗粒回收任务来评估这一假设。小井任务需要熟练的数字使用，导致更高的效率，小球检索的小井组。这是通过在远端前肢（手指）皮质代表区的扩展和近端（手腕/前臂）代表区的减少来实现的。大孔组动物执行重复的、非熟练的活动，并且在皮质图中没有显示出任何变化。因此，学习一项技能是触发重组的关键因素。然而，尚未解决远端运动表示的扩展是否伴随着遭受收缩的运动表示（即手腕/前臂）的性能恶化。随着越来越多的重点被放在运动学习为基础的范例在治疗患有中枢神经系统病变的个人，它变得越来越重要，以了解是否有利的扩展与功能改善的一个部分（如手）康复后，诱导有害的影响，在未经训练的部分，遭受减少的代表（如肘）的功能。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Neuroplastic changes in the brain include enduring reorganization (Boroojerdi et al., 2001) attributable to the dynamic circuitry of the cortex (Sanes and Donoghue, 2000). Rehabilitation research involving individuals with neurological impairments, especially stroke, is placing greater emphasis on training paradigms promoting such changes in the brain (Carey et al., 2002; Carey et al., 2004; Gow et al., 2004; Koski et al., 2004; Liepert et al., 2000). However, understanding of the mechanisms of reorganization following rehabilitation is still far from complete. Complex skill acquisition or skill re-learning can promote neuroplastic representational changes at the level of the motor cortex, often referred to as the "learning-dependent hypothesis" (Kleim et al., 1998; Plautz et al., 2000). Plautz et al. (2000) evaluated this hypothesis by training squirrel monkeys on either a complex, small-well pellet retrieval task or on a simple, large-well pellet retrieval task respectively. The small-well task required skilled digit use that led to greater efficiency of pellet-retrieval in the small-well group. This was paralleled by expansion in distal forelimb (digit) cortical representational area with reduction in proximal (wrist/forearm) representation. The large-well group animals executed repetitive, unskilled activity and failed to demonstrate any changes in cortical maps. Thus, learning of a skill is the key element in triggering reorganization. However, it has not been addressed whether the expansion of distal movement representations was accompanied by deterioration in performance of the movement representations that suffered a contraction, viz. wrist/forearm. As more and more emphasis is being laid on motor learning based paradigms in treatment of individuals with lesions of the CNS, it is becoming increasingly important to know whether favorable expansion of representations associated with functional improvements for a segment (e.g. hand) following rehabilitation, induces deleterious effects on function at untrained segments that suffer a reduction in representation (e.g. elbow).