美国纽约大学Michael A. Long等研究人员合作发现，运动皮层动态的时间标度揭示发声的分级控制。2024年1月30日，《自然—神经科学》杂志在线发表了这项成果。

在高发声啮齿类动物（艾斯顿唱歌鼠）中，研究人员揭示了口面部运动皮层（OMC）的神经动态，这是一个对发声行为至关重要的结构。研究人员首先描述了受音符成分（约100毫秒）调节的神经活动，这可能代表了感觉反馈。然而，在更长的时间尺度上，OMC神经元表现出多种多样且经常持续的前运动脉冲模式，这些模式随着歌曲持续时间（约10秒）的延长或压缩而伸展。

通过计算建模，研究人员证明了这种时间缩放通过下游的运动生产回路发挥作用，可以实现发声的灵活性。这些结果为研究分层控制回路提供了一个框架，分层控制回路是许多自然和人工系统的共同设计原则。

据悉，神经皮层活动被认为介导了对发声的自主控制，但其潜在的神经机制仍不清楚。

附：英文原文

Title: Temporal scaling of motor cortical dynamics reveals hierarchical control of vocal production

Author: Banerjee, Arkarup, Chen, Feng, Druckmann, Shaul, Long, Michael A.

Issue&Volume: 2024-01-30

Abstract: Neocortical activity is thought to mediate voluntary control over vocal production, but the underlying neural mechanisms remain unclear. In a highly vocal rodent, the male Alston’s singing mouse, we investigate neural dynamics in the orofacial motor cortex (OMC), a structure critical for vocal behavior. We first describe neural activity that is modulated by component notes (~100ms), probably representing sensory feedback. At longer timescales, however, OMC neurons exhibit diverse and often persistent premotor firing patterns that stretch or compress with song duration (~10s). Using computational modeling, we demonstrate that such temporal scaling, acting through downstream motor production circuits, can enable vocal flexibility. These results provide a framework for studying hierarchical control circuits, a common design principle across many natural and artificial systems.

DOI: 10.1038/s41593-023-01556-5

Source: https://www.nature.com/articles/s41593-023-01556-5