The classical view on motor control makes a clear distinction between the role of motor cortex in controlling muscles and parietal cortex in processing movement plans and goals. However, the strong parieto-frontal connections argue against such clear-cut separation of function. Modern dynamical approaches revealed that population activity in motor cortex can be captured by a limited number of patterns, called neural states that are preserved across diverse motor behaviors. Whether such dynamics are also present in parietal cortex is unclear. Here, we studied neural dynamics in the primate parietal cortex during arm movements and found three main states temporally coupled to the planning, execution and target holding epochs. Strikingly, as reported recently in motor cortex, execution was subdivided into distinct, arm acceleration- and deceleration-related, states. These results suggest that dynamics across parieto-frontal areas are highly consistent and hint that parietal population activity largely reflects timing constraints while motor actions unfold.

关于运动控制的经典观点明确区分了运动皮层在控制肌肉中的作用和顶叶皮层在处理运动计划和目标中的作用。然而，强烈的顶叶连接反对这种明确的功能分离。现代动力学方法表明，运动皮层中的群体活动可以被有限数量的模式捕获，称为神经状态，这些模式在不同的运动行为中得以保留。这种动力学是否也存在于顶叶皮质中尚不清楚。在这里，我们研究了灵长类动物顶叶皮层在手臂运动期间的神经动力学，发现三个主要状态在时间上与计划、执行和目标保持时期相关联。引人注目的是，正如最近在运动皮层中报道的那样，执行被细分为不同的，手臂加速和减速相关的状态。这些结果表明，顶叶区域的动态是高度一致的，并暗示顶叶种群活动在很大程度上反映了运动动作展开时的时间限制。