ENCODING MOVEMENT KINEMATICS IN THE PREMOTOR CORTEX

了解中枢神经系统在正常和非智力障碍中的作用 异常的运动行为需要破译哪些参数 运动的表现以及在哪里。心理物理观察支持 假设到达动作是计划和/或执行的 运动学框架。在运动学上，方向、距离、速度和 动作的精确度是将手臂定位在 太空。而神经元与运动方向的相关性已经被研究 并在几个大脑皮层区域进行了描述，中央 其他手臂运动参数的表示收到的较少 请注意。本提案将评估有关编码的五个问题 灵长类运动前神经元放电的运动学参数。 重点放在确定贡献和关系上 距离、方向、速度和空间精度之间的关系 三维手臂完成任务。在第一个具体目标中， 运动前神经元活动与空间精确度的关系 将对一个动作进行评估。在第二个具体目标中，一个二维的 将使用跟踪任务来剖析相对重要性和 流速、距离和移动时间对流量的交互作用 运动前皮质细胞。在第三个特定目标中，神经元 运动幅度的相关性将在三维空间中进行研究 正在完成任务。在第四个具体目标中，我们提出了系统地 改变视觉反馈，在动作中引入错误。vbl.使用 这项复杂的、视觉指导的任务，将决定是否 距离和方向的编码保持不变，并且 视觉运动“错误”编码在这些细胞的放电中。最后，在 第五个特定的目标是运动前皮质被假设扮演一个 在学习将运动与运动相结合的任意关联中的作用 刺激。使用一种需要按比例调整运动的学习范式 由于反馈的变化，我们建议研究如何适应 移动方向和距离在单个单元级别进行编码。 总体而言，这些研究将更好地定义运动前皮质的作用 在运动行为中发挥作用。

Understanding the role of the central nervous system in the normal and abnormal motor behavior will require deciphering what parameters of movement are represented and where. Psychophysical observations support the hypothesis that reaching movements are planned and/or executed using a kinematic framework. Kinematically the direction, distance, velocity and accuracy of a movement are crucial components to positioning the arm in space. While neuronal correlates of movement direction have been studied and described in several cerebral cortical areas, the central representation of other arm movement parameters has received less attention. This proposal will evaluate five issues focused on the encoding of kinematic parameters in the discharge of primate premotor neurons. Emphasis is placed on determining the contributions and relationships between distance, direction, velocity and spatial accuracy in two and three dimensional arm reaching tasks. In the first Specific Aim the dependence of the activity of premotor neurons on the spatial accuracy of a movement will be evaluated. In the second Specific Aim a two dimensional tracking task will be used to dissect out relative importance and interactions between velocity, distance and movement time to the discharge of premotor cortical cells. In the third Specific Aim the neuronal correlates of movement amplitude will be studied in a three dimensional reaching task. In the fourth Specific Aim we propose to systematically alter the visual feedback, introducing errors into the movement. Using this complex, visually guided task, it will be determined whether the encoding of distance and direction remains invariant and whether the visuomotor "errors" are encoded in these cells' discharge. Lastly, in the fifth Specific Aim the premotor cortex has been hypothesized to play a role in learning the arbitrary associations that couple a movement to a stimulus. Using a learning paradigm which requires the scaling of movement kinematics due to a feedback change, we propose to study how adaptation of movement direction and distance is encoded at the single cell level. Overall, these studies will better define the role the premotor cortex plays in motor behavior.