Bruno Angela M, Frost William N, Humphries Mark D
Department of Neuroscience, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064-3095, USA.
Department of Cell Biology and Anatomy, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064-3095, USA.
Neuron. 2015 Apr 8;86(1):304-18. doi: 10.1016/j.neuron.2015.03.005. Epub 2015 Mar 26.
The neural substrates of motor programs are only well understood for small, dedicated circuits. Here we investigate how a motor program is constructed within a large network. We imaged populations of neurons in the Aplysia pedal ganglion during execution of a locomotion motor program. We found that the program was built from a very small number of dynamical building blocks, including both neural ensembles and low-dimensional rotational dynamics. These map onto physically discrete regions of the ganglion, so that the motor program has a corresponding modular organization in both dynamical and physical space. Using this dynamic map, we identify the population potentially implementing the rhythmic pattern generator and find that its activity physically traces a looped trajectory, recapitulating its low-dimensional rotational dynamics. Our results suggest that, even in simple invertebrates, neural motor programs are implemented by large, distributed networks containing multiple dynamical systems.
对于小型的特定电路，运动程序的神经基质已得到很好的理解。在此，我们研究运动程序是如何在大型网络中构建的。我们在执行运动程序期间对海兔足神经节中的神经元群体进行成像。我们发现该程序由极少数动态构建块构建而成，包括神经集群和低维旋转动力学。这些映射到神经节的物理离散区域，因此运动程序在动态和物理空间中都具有相应的模块化组织。利用这一动态图谱，我们识别出可能实现节律模式发生器的群体，并发现其活动在物理上描绘出一条环状轨迹，概括了其低维旋转动力学。我们的结果表明，即使在简单的无脊椎动物中，神经运动程序也是由包含多个动态系统的大型分布式网络实现的。
