Neural Mechanisms of Planning and Control of Movement

描述：(申请人提供) 这项研究的长期目标是阐明大脑是如何 在启动马达响应之前的运动参数，将这些 参数，并在移动执行期间监视它们。 这些过程不断地在许多人的行为技能中使用 动物物种，例如在各种活动中，如狩猎猎物或 打网球。然而，到目前为止，人们对 与运动修正相关的神经生理学机制 参数。与大脑皮质相关的神经元的活动 恒河猴手臂动作的准备和执行将被记录下来 当他们执行特定的任务时。这些区域包括主马达 大脑皮质、背侧运动前皮质和后顶叶皮质，它们是 被认为是神经网络中的基本节点，参与规划和 执行动作。计划了一系列任务来研究神经 与指定移动参数相关联的进程，以及 根据需要对此表示进行转换，以响应 环境。第一组任务需要离散的指向臂 向切换位置的可视目标移动，或连续跟踪 指先朝一个方向移动，然后突然变化的移动目标 方向。在这两种情况下，视觉上指定的移动方向都是 在移动之前或移动过程中的某个点进行修改，并需要 电机响应规格的相应变化。这些任务包括 旨在描述参与定义的神经元活动的模式 以及更新马达输出的可视指定目标。在前两个 上面提到的任务，在之前的任何时候都只有一个视觉刺激 或在运动反应期间，因此反应的目的总是 明确地定义。然而，多个替代方案也很常见 对于即将到来的马达响应，在实际选择之前进行考虑 并被处死。例如，在狩猎时，猎物可能会被认为 在某些方向或在打网球时更有可能逃脱 对方球员的回应是以一定的角度传球 比其他人更好。准备活动的神经过程将通过以下方式进行研究 使用预先提示范式：两个刺激指示两种可能的选择 将显示响应，延迟一段时间后，其中一个将变为实际响应 目标神经活动的分析将解决什么问题 筹备活动的特点，特别是与 可供选择的反应之间的差异程度；这是如何 当选择其中一种可选的运动反应时，活动被转换。 在所有计划中的实验中，将对神经元活动进行研究 在单细胞和种群水平上。这一分析将有助于 描述运动参数的神经表示的动力学， 特别是方向和幅度，而它是在引爆之前形成的 运动的一部分，虽然它是为了响应 这项任务。

DESCRIPTION:(provided by applicant) The long term goal of this research is to elucidate how the brain specifies movement parameters before the initiation of a motor response, transforms these parameters when needed, and monitors them during the execution of a movement. These processes are incessantly used in the behavioral repertoire of many animal species, for example in activities as diverse as hunting preys or playing tennis. However, little attention has been given so far to the neurophysiological mechanisms associated with the amendment of movement parameters. The activity of neurons from cortical areas related to the preparation and execution of arm movements will be recorded in rhesus monkeys while they perform in specific tasks. These areas include the primary motor cortex, the dorsal premotor cortex and the posterior parietal cortex, which are considered essential nodes in the neural network engaged in planning and executing movements. A series of tasks was planned to investigate the neural processes associated with specifying movement parameters, and the transformation of this representation as needed in response to changes in the environment. A first group of tasks requires either discrete pointing arm movements toward a visual target that switches position, or continuous tracking of a moving target that moves first in one direction and then suddenly changes direction. In both cases the visually specified direction of movement is modified at some point either before or during the movement and requires a corresponding change in the specification of the motor response. The tasks are designed to characterize the patterns of neuronal activity engaged in defining and updating the visually specified goal of the motor output. In the first two tasks mentioned above, only one visual stimulus is present at any time before or during the motor response, and therefore the aim of the response is always unambiguously defined. However, it is also common that multiple alternatives for the upcoming motor response are considered before one is actually selected and executed. For example, while hunting it may be expected that the prey is more likely to escape in some directions than others, or while playing tennis that the opponent player responds by sending the ball at some angles rather than others. The neural process of preparatory activity will be investigated by using a precuing paradigm: two stimuli indicating two alternative possible responses are displayed, and after a delay one of them will become the actual target The analysis of the neural activity will address the questions of what are the characteristics of the preparatory activity, in particular in relation with the degree of disparity between the alternative responses; and how is this activity transformed when one of the alternative motor responses is selected. In all the experiments planned, the neuronal activity will be investigated both at the single-cell and population level. The analysis will serve to characterize the dynamics of the neural representation of movement parameters, in particular direction and amplitude, while it is formed before the initiation of the movement, and while it is transformed in response to the requirements of the task.