Motor cortex is required for flexible but not automatic motor sequences.
Motor cortex is required for flexible but not automatic motor sequences.
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运动皮层对于灵活但非自动的运动序列是必需的。
DOI：
10.1101/2023.09.05.556348
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Ölveczky,BenceP
中科院分区：
文献类型：
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作者：
Mizes,KevinGC;Lindsey,Jack;Escola,GSean;Ölveczky,BenceP
运动皮层对运动序列执行的贡献是有争议的，研究支持不同的观点。在这里，我们探讨运动皮层的参与程度取决于任务的要求，特别是它的作用是否不同的高度实践，或“自动”，序列与灵活的序列通知外部事件。为了验证这一点，我们训练大鼠产生三元素运动序列，要么通过对单个序列进行过度训练，要么让它们遵循指导性的视觉线索。损伤运动皮层表明，它是必要的灵活的线索驱动的运动序列，但孤立训练的单一自动行为的依赖。然而，当一个自动的运动序列一起练习灵活的任务，它成为运动皮层依赖，这表明皮层下巩固的自动运动序列被延迟或阻止时，同样的序列也产生了灵活的上下文。一个简单的神经网络模型概括了这些结果，并解释了潜在的电路机制。我们的研究结果批判性地描绘了运动皮层在运动序列执行中的作用，描述了它所从事的条件和它所履行的功能，从而调和了运动皮层在运动序列生成中的作用似乎相互矛盾的观点。
How motor cortex contributes to motor sequence execution is much debated, with studies supporting disparate views. Here we probe the degree to which motor cortex’s engagement depends on task demands, specifically whether its role differs for highly practiced, or ‘automatic’, sequences versus flexible sequences informed by external events. To test this, we trained rats to generate three-element motor sequences either by overtraining them on a single sequence or by having them follow instructive visual cues. Lesioning motor cortex revealed that it is necessary for flexible cue-driven motor sequences but dispensable for single automatic behaviors trained in isolation. However, when an automatic motor sequence was practiced alongside the flexible task, it became motor cortex-dependent, suggesting that subcortical consolidation of an automatic motor sequence is delayed or prevented when the same sequence is produced also in a flexible context. A simple neural network model recapitulated these results and explained the underlying circuit mechanisms. Our results critically delineate the role of motor cortex in motor sequence execution, describing the condition under which it is engaged and the functions it fulfills, thus reconciling seemingly conflicting views about motor cortex’s role in motor sequence generation.