MOTOR AND COMPLEX FUNCTIONS OF BASAL GANGLIA AND CORTEX

本建议涉及的主要问题是：1）电机是否 基底神经节-丘脑皮质“运动回路”内的处理是 在神经元水平上，主要以串行或并行方式组织， 2）是否有系统的转变，在连续的 电路的各个阶段，在变量的神经表征中， 涉及运动处理的不同功能“水平”。 的 拟议的研究旨在确定a）是否相同的类别 信息（即，相同的电动机变量）被提出在不同的 “运动回路”的阶段（皮质、纹状体、苍白球、丘脑）; B） 是否有系统的变化，在比例代表性， 由电路的连续级处的神经元产生的给定运动变量;以及 c）是否有系统的转变，在连续的阶段， 电路，在回归斜率相关的变量特定的变化， 神经元放电率在所表示的变量中的分级。 的 本项目的具体目标如下：[1]确定， 在视觉引导的肢体运动的计划和执行期间， 运动处理的多个“层次”并行地表示为： 每个中央前运动场内的神经元活动， 为“汽车电路”做贡献。 单个神经元的活动 SMA、MC和阿帕将记录在执行任务的猴中， 他们作出达到运动定位光标在二维 空间 这些任务包括准备和执行“模式”， 运动处理，也将分离变量相关的不同 处理的“层次”，即目标层次变量、轨迹/运动学 变量和动态/肌肉相关变量。 三个领域的数据 然后根据分类和回归的结果进行比较 分析。 [2]为了确定在规划和执行过程中， 视觉引导的肢体运动，多个“层次”的运动处理， 在纹状体阶段的神经元活动的平行代表， “电机电路”。 与任务相关的单个单元活动将从 猴子的壳核的臂区， 具体目标1。 在进行了相同的分析后， 数据将与具体目标1中获得的数据进行比较。 [3]到 确定在规划和执行视觉引导期间， 肢体运动，多个“层次”的运动处理表示在 与苍白球阶段的“运动回路”的神经元活动平行。 与任务相关的单个单位活动将从手臂区域取样， GPi在执行特定目标1和2中使用的相同任务的猴子中。 这些数据将与具体目标2中获得的数据进行比较， 以与比较壳核和皮质数据相同的方式。 [4]到 确定在规划和执行视觉引导期间， 肢体运动，多个“层次”的运动处理表示在 与“运动回路”的丘脑阶段的神经元活动平行。 与任务相关的单个单元活动将从以下区域中取样： 执行特定目标1-3中所用相同任务的猴子中的VLo。 这些 将对数据进行与上述相同的分析， 其中a）来自具体目标1的SMA数据，和B）来自具体目标1的GPi数据。 具体目标3。

The principal issues addressed in this proposal are: 1) whether motor processing within the basal ganglia-thalamocortical `motor circuit' is organized, at the neuronal level, in a predominantly serial or parallel fashion; and 2) whether there are systematic transformations, at successive stages of the circuit, in the neural representations of variables that have been implicated in different functional `levels' of motor processing. The proposed studies are designed to determine a) whether the same categories of information (i.e., the same motor variables) are proposed at different stages (cortical, striatal, pallidal, thalamic) of the `motor circuit'; b) whether there are systematic changes in the proportionate representation of a given motor variable by neurons at successive stages of the circuit; and c) whether there are systematic shifts, at successive stages of the circuit, in the regression slopes relating variable-specific changes in neuronal discharge rates to gradations in the represented variables. The Specific Aims for the project are as follows: [1] To determine whether, during the planning and execution of visually guided limb movements, multiple `levels' of motor processing are represented in parallel by neuronal activity within each of the precentral motor fields that contribute to the `motor circuit'. The activity of individual neurons in SMA, MC and APA will be recorded in monkeys performing tasks that require them to make reaching movements to position a cursor in two-dimensional space. The tasks involve both the preparation and execution `modes' of motor processing, and will also dissociate variables relevant to different `levels' of processing viz, target level variables, trajectory/kinematic variables, and dynamic/muscle-related variables. Data from the three areas will then be compared, based on results of both categorical and regression analyses. [2] To determine whether, during the planning and execution of visually guided limb movements, multiple `levels' of motor processing are represented in parallel by neuronal activity at the striatal stage of the `motor circuit'. Task-related single unit activity will be sampled from the arm region of the putamen in monkeys performing the same tasks employed in Specific Aim 1. After being subjected to the same set of analyses, the data will be compared with those obtained in Specific Aim 1. [3] To determine whether, during the planning and execution of visually guided limb movements, multiple `levels' of motor processing are represented in parallel by neuronal activity at the pallidal stage of the `motor circuit'. Task-related single unit activity will be sampled from the arm region of GPi in monkeys performing the same tasks used in Specific Aims 1 and 2. These data will be compared with those obtained in Specific Aim 2, in the same manner as the putamen and cortical data are to be compared. [4] To determine whether, during the planning and execution of visually guided limb movements, multiple `levels' of motor processing are represented in parallel by neuronal activity at the thalamic stage of the `motor circuit'. Task-related single unit activity will be sampled from the are region of VLo in monkeys performing the same tasks used in Specific Aims 1-3. These data will be subjected to the same analyses outlined above, and compared with both a) the SMA data from Specific Aim 1, and b) the GPi data from Specific Aim 3.