NYU Neuroscience Institute and Department of Otolaryngology, New York University Langone Medical Center, New York, NY 10016, USA; Center for Neural Science, New York University, New York, NY 10003, USA.
Department of Physics and Center for Neural Engineering, Pennsylvania State University, University Park, PA 16802, USA.
Cell. 2020 Oct 15;183(2):537-548.e12. doi: 10.1016/j.cell.2020.09.019.
Sequential activation of neurons has been observed during various behavioral and cognitive processes, but the underlying circuit mechanisms remain poorly understood. Here, we investigate premotor sequences in HVC (proper name) of the adult zebra finch forebrain that are central to the performance of the temporally precise courtship song. We use high-density silicon probes to measure song-related population activity, and we compare these observations with predictions from a range of network models. Our results support a circuit architecture in which heterogeneous delays between sequentially active neurons shape the spatiotemporal patterns of HVC premotor neuron activity. We gauge the impact of several delay sources, and we find the primary contributor to be slow conduction through axonal collaterals within HVC, which typically adds between 1 and 7.5 ms for each link within the sequence. Thus, local axonal "delay lines" can play an important role in determining the dynamical repertoire of neural circuits.
在各种行为和认知过程中都观察到了神经元的顺序激活，但潜在的电路机制仍知之甚少。在这里，我们研究了成年斑马雀前脑 HVC（专有名词）中的前运动序列，这些序列是执行时间精确的求偶歌曲的核心。我们使用高密度硅探针来测量与歌曲相关的群体活动，并将这些观察结果与一系列网络模型的预测进行比较。我们的结果支持这样一种电路结构，即顺序激活的神经元之间的异质延迟形成了 HVC 前运动神经元活动的时空模式。我们评估了几个延迟源的影响，发现主要贡献者是 HVC 中轴突侧支的缓慢传导，这通常在序列中的每个链接上增加 1 到 7.5 毫秒。因此，局部轴突“延迟线”可以在确定神经电路的动态范围方面发挥重要作用。
