Department of Neuroscience, Columbia University Medical Center, New York, NY, USA.
Zuckerman Institute, Columbia University, New York, NY, USA.
Nat Neurosci. 2021 Mar;24(3):412-424. doi: 10.1038/s41593-021-00798-5. Epub 2021 Feb 22.
Rapid execution of motor sequences is believed to depend on fusing movement elements into cohesive units that are executed holistically. We sought to determine the contribution of primary motor and dorsal premotor cortex to this ability. Monkeys performed highly practiced two-reach sequences, interleaved with matched reaches performed alone or separated by a delay. We partitioned neural population activity into components pertaining to preparation, initiation and execution. The hypothesis that movement elements fuse makes specific predictions regarding all three forms of activity. We observed none of these predicted effects. Rapid two-reach sequences involved the same set of neural events as individual reaches but with preparation for the second reach occurring as the first was in flight. Thus, at the level of dorsal premotor and primary motor cortex, skillfully executing a rapid sequence depends not on fusing elements, but on the ability to perform two key processes at the same time.
人们认为，快速执行运动序列依赖于将运动元素融合成整体执行的有凝聚力的单元。我们试图确定初级运动皮层和背侧运动前皮层对这种能力的贡献。猴子执行高度熟练的两个触及序列，穿插着单独执行或通过延迟分开的匹配触及。我们将神经群体活动分为与准备、启动和执行有关的成分。运动元素融合的假设对所有三种形式的活动都有具体的预测。我们没有观察到这些预测的效果。快速的两个触及序列涉及到相同的一组神经事件，就像单独的触及一样，但对第二个触及的准备是在第一个触及飞行的过程中进行的。因此，在背侧运动前皮层和初级运动皮层的水平上，熟练地执行快速序列并不依赖于元素的融合，而是依赖于同时执行两个关键过程的能力。
