Animal behavior is organized into nested temporal patterns that span multiple timescales. This behavior hierarchy is believed to arise from a hierarchical neural architecture: Neurons near the top of the hierarchy are involved in planning, selecting, initiating, and maintaining motor programs, whereas those near the bottom of the hierarchy act in concert to produce fine spatiotemporal motor activity. In Caenorhabditis elegans , behavior on a long timescale emerges from ordered and flexible transitions between different behavioral states, such as forward, reversal, and turn. On a short timescale, different parts of the animal body coordinate fast rhythmic bending sequences to produce directional movements. Here, we show that Sublateral Anterior A (SAA), a class of interneurons that enable cross-communication between dorsal and ventral head motor neurons, play a dual role in shaping behavioral dynamics on different timescales. On a short timescale, SAA regulate and stabilize rhythmic bending activity during forward movements. On a long timescale, the same neurons suppress spontaneous reversals and facilitate reversal termination by inhibiting Ring Interneuron M (RIM), an integrating neuron that helps maintain a behavioral state. These results suggest that feedback from a lower-level cell assembly to a higher-level command center is essential for bridging behavioral dynamics at different levels.

中文翻译：

---

由一类中间神经元进行的分层行为控制


动物行为被组织成跨越多个时间尺度的嵌套时间模式。这种行为层次结构被认为源于分层神经架构：靠近层次结构顶部的神经元参与规划、选择、启动和维护运动程序，而靠近层次结构底部的神经元协同作用以产生精细的时空运动活动。在秀丽隐杆线虫中，长期行为出现在不同行为状态之间的有序和灵活的过渡中，例如向前、反转和转向。在短时间内，动物身体的不同部位协调快速有节奏的弯曲序列，以产生定向运动。在这里，我们表明 Sublateral Anterior A （SAA） 是一类能够在背侧和腹侧头部运动神经元之间交叉交流的中间神经元，在不同时间尺度上塑造行为动力学方面发挥着双重作用。在短时间内，SAA 调节和稳定向前运动期间的节律性弯曲活动。在很长的时间尺度上，相同的神经元通过抑制环形中间神经元 M （RIM） 来抑制自发逆转并促进逆转终止，RIM 是一种有助于维持行为状态的整合神经元。这些结果表明，从较低级别的单元组件到较高级别的指挥中心的反馈对于桥接不同级别的行为动力学至关重要。