NEURAL AND MUSCULAR CONTROL OF FINGER MOVEMENTS

描述：（改编自研究者摘要）移动 手指相对独立地使人类和非人类能够 灵长类动物操纵环境中的各种物体，并执行 各种各样的动作和姿势。运动皮层的病变，如 与中风相关的那些，引起衰弱和持续的缺陷， 即使弯曲的能力 并将手指一起伸展恢复。因此，许多科学 人们的注意力已经转向理解大脑的运动中心是如何 赋予分别控制手指的能力。的功能 然而，外周运动装置在很大程度上被忽视， 解释与运动皮层组织相关的发现。在 特别地，主要负责移动手指的致动器是 单腹肌肉产生远端的多个肌腱， 所有的手指。虽然目前的观点是这些多末端肌肉 由不同的功能区组成，这些功能区控制着不同的运动， 数字，调查人员最近表明，运动单位的力量，在这些 肌肉不是集中在单个肌腱上，而是广泛分布 穿过许多肌腱这一观察提出了一些关于 神经和肌肉控制的手指，是解决在具体的 这一提议的目的。第一，什么样的具体因素有助于分散 运动单位力在控制肌肉的多个肌腱上的作用 手指？第二，手指实际上可以移动到什么程度 独立地。第三，神经系统采用什么策略 当试图移动一根手指时， 手指的独立驱动器这些问题将在人类 使用各种电生理学和生物力学技术， 包括神经内和肌内微刺激、交叉相关 分析同时活动的运动单位记录的尖峰序列， 运动学分析和多块肌肉的肌电图记录 在执行个性化的手指运动期间。结果从这些 研究将增加我们对脊椎和肌肉系统 在手指运动的阐述中是协调的，并将提供一个 理解运动皮层如何指定自愿的重要框架 手的动作。

DESCRIPTION: (adapted from Investigator's abstract) The ability to move the fingers relatively independently of one another enables human and non-human primates to manipulate diverse objects in the environment and to execute an immense variety of movements and gestures. Lesions of the motor cortex, such as those associated with stroke, give rise to debilitating and persistent deficits in the ability to move fingers individually even though the capacity to flex and extend the fingers together recovers. Accordingly, much scientific attention has been directed toward understanding how motor centers of the brain impart the ability to separately control the fingers. The function of the peripheral motor apparatus, however, has been largely ignored in the interpretation of findings related to the organization of the motor cortex. In particular, the actuators primarily responsible for moving the fingers are single-bellied muscles that give rise distally to multiple tendons that insert onto all the fingers. While the current view is that these multiendoned muscles consist of distinct functional compartments that govern the motion of different digits, the investigators have recently shown that motor unit force in these muscles is not concentrated on a single tendon but is broadly distributed across many tendons. This observation promotes a number of questions about the neural and muscular control of the fingers that are addressed in the specific aims of this proposal. First, what specific factors contribute to the dispersal of motor unit force across multiple tendons in muscles that control the fingers? Second, to what extent is it actually possible to move the fingers independently. And third, what strategies are employed by the nervous system when attempting to move a single finger given the apparent absence of independent actuators of the digits? These questions will be addressed in human subjects using a variety of electrophysiological and biomechanical techniques, including intraneural and intramuscular microstimulation, cross-correlation analysis of spike trains recorded from concurrently active motor units, kinematic analysis, and electromyographic recordings from multiple muscles during the execution of individuated finger movements. The results from these studies will add to our comprehension of how the spinal and muscular systems are coordinated in the elaboration of finger movements and will provide an important framework for understanding how the motor cortex specifies voluntary motion of the hand.