Motor cortical representation of speed and direction during reaching
Motor cortical representation of speed and direction during reaching
复制标题
DOI：
10.1152/jn.1999.82.5.2676
复制
发表时间：
1999-11-01
影响因子：
2.5
通讯作者：
Schwartz, AB
中科院分区：
文献类型：
--
作者：
Moran, DW;Schwartz, AB
当猴子的手从中心位置移动到围绕一个圆圈的八个目标中的一个时，研究人员研究了与伸手相关的运动皮质基质。单细胞活动模式记录在运动皮层的近臂区域在任务期间。除了单细胞活动的平均方向选择性（“首选方向”）得到充分研究外，我们还发现运动的时变速度可以在皮层活动中表现出来。建立了运动皮质放电率与这两个参数之间的单一方程。这个方程既有独立的（仅速度）成分，也有交互的（速度和方向）成分，它描述了任务过程中大部分随时间变化的运动皮层活动。在这项任务中，记录了一些上臂肌肉的肌电活动。肌肉活动也被发现是有方向性的；然而，优选方向的分布被发现明显不同于皮层活动。此外，速度对皮质和肌肉活动的影响也有显著差异。
The motor cortical substrate associated with reaching was studied as monkeys moved their hands from a central position to one of eight targets spaced around a circle. Single-cell activity patterns were recorded in the proximal arm area of motor cortex during the task. In addition to the well-studied average directional selectivity ("preferred direction") of single-cell activity, we also found the time-varying speed of movement to be represented in the cortical activity. A single equation relating motor cortical discharge rate to these two parameters was developed. This equation, which has both independent (speed only) and interactive (speed and direction) components, described a large portion of the time-varying motor cortical activity during the task. Electromyographic activity from a number of upper arm muscles was recorded during this task. Muscle activity was also found to be directionally tuned; however, the distributions of preferred directions were found to be significantly different from cortical activity. Tn addition, the effect of speed on cortical and muscle activity was also found to be significantly different.