Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, University of Science and Technology of China, Hefei 230027, People's Republic of China
Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, People's Republic of China.
Philos Trans R Soc Lond B Biol Sci. 2018 Sep 10;373(1758):20170370. doi: 10.1098/rstb.2017.0370.
The intrinsic oscillatory activity of central pattern generators underlies motor rhythm. We review and discuss recent findings that address the origin of motor rhythm. These studies propose that the A- and mid-body B-class excitatory motor neurons at the ventral cord function as non-bursting intrinsic oscillators to underlie body undulation during reversal and forward movements, respectively. Proprioception entrains their intrinsic activities, allows phase-coupling between members of the same class motor neurons, and thereby facilitates directional propagation of undulations. Distinct pools of premotor interneurons project along the ventral nerve cord to innervate all members of the A- and B-class motor neurons, modulating their oscillations, as well as promoting their bi-directional coupling. The two motor sub-circuits, which consist of oscillators and descending inputs with distinct properties, form the structural base of dynamic rhythmicity and flexible partition of the forward and backward motor states. These results contribute to a continuous effort to establish a mechanistic and dynamic model of the sensorimotor system. exhibits rich sensorimotor functions despite a small neuron number. These findings implicate a circuit-level functional compression. By integrating the role of rhythm generation and proprioception into motor neurons, and the role of descending regulation of oscillators into premotor interneurons, this numerically simple nervous system can achieve a circuit infrastructure analogous to that of anatomically complex systems. has manifested itself as a compact model to search for general principles of sensorimotor behaviours.This article is part of a discussion meeting issue 'Connectome to behaviour: modelling at cellular resolution'.
中枢模式发生器的内在振荡活动是运动节律的基础。我们回顾并讨论了最近的发现，这些发现解决了运动节律的起源问题。这些研究提出，腹侧脊髓中的 A 型和中体 B 型兴奋性运动神经元作为非爆发性内在振荡器，分别为反转和前进运动期间的身体波动提供基础。本体感受使它们的内在活动同步，允许同一类运动神经元成员之间的相位耦合，从而促进波动的定向传播。不同的运动前中间神经元池沿腹神经索投射，以支配 A 型和 B 型运动神经元的所有成员，调节它们的振荡，并促进它们的双向耦合。这两个运动子电路由振荡器和具有不同特性的下行输入组成，为动态节律性和前后运动状态的灵活划分提供了结构基础。这些结果有助于建立感觉运动系统的机械和动态模型的持续努力。尽管神经元数量较少，但它表现出丰富的感觉运动功能。这些发现暗示了一种电路级别的功能压缩。通过将节律产生和本体感受的作用整合到运动神经元中，以及将振荡器的下行调节作用整合到运动前中间神经元中，这个数字简单的神经系统可以实现类似于解剖复杂系统的电路基础设施。已经表现为一种紧凑的模型，用于搜索感觉运动行为的一般原理。本文是“连接组到行为：以细胞分辨率建模”讨论会议的一部分。
