To advance the measurement of distributed neuronal population representations of targeted motor actions on single trials, we developed an optical method (COSMOS) for tracking neural activity in a largely uncharacterized spatiotemporal regime. COSMOS allowed simultaneous recording of neural dynamics at ∼30 Hz from over a thousand near-cellular resolution neuronal sources spread across the entire dorsal neocortex of awake, behaving mice during a three-option lick-to-target task. We identified spatially distributed neuronal population representations spanning the dorsal cortex that precisely encoded ongoing motor actions on single trials. Neuronal correlations measured at video rate using unaveraged, whole-session data had localized spatial structure, whereas trial-averaged data exhibited widespread correlations. Separable modes of neural activity encoded history-guided motor plans, with similar population dynamics in individual areas throughout cortex. These initial experiments illustrate how COSMOS enables investigation of large-scale cortical dynamics and that information about motor actions is widely shared between areas, potentially underlying distributed computations.

为了推进对单个试验中目标运动动作的分布式神经元群体表示的测量，我们开发了一种光学方法 (COSMOS)，用于在很大程度上未表征的时空机制中跟踪神经活动。COSMOS 允许在 ~30 Hz 下同时记录神经动力学，来自超过一千个近细胞分辨率神经元来源，这些神经元来源分布在清醒的整个背侧新皮层，在三选项舔目标任务中表现良好的小鼠。我们确定了跨越背侧皮质的空间分布的神经元群体表征，这些表征精确编码了单个试验中正在进行的运动动作。使用未平均的全会话数据以视频速率测量的神经元相关性具有局部空间结构，而试验平均数据表现出广泛的相关性。神经活动的可分离模式编码历史引导的运动计划，在整个皮层的各个区域具有相似的种群动态。这些初步实验说明了 COSMOS 如何支持大规模皮层动力学的研究，以及有关电机动作的信息在区域之间广泛共享，这可能是分布式计算的基础。