Gamma oscillations are thought to coordinate the spike timing of functionally specialized neuronal ensembles across brain regions. To test this hypothesis, we optogenetically perturbed gamma spike timing in the rat medial (MEC) and lateral (LEC) entorhinal cortices and found impairments in spatial and object learning tasks, respectively. MEC and LEC were synchronized with the hippocampal dentate gyrus through high- and low-gamma-frequency rhythms, respectively, and engaged either granule cells or mossy cells and CA3 pyramidal cells in a task-dependent manner. Gamma perturbation disrupted the learning-induced assembly organization of target neurons. Our findings imply that pathway-specific gamma oscillations route task-relevant information between distinct neuronal subpopulations in the entorhinal-hippocampal circuit. We hypothesize that interregional gamma-time-scale spike coordination is a mechanism of neuronal communication.

伽马振荡被认为可以协调大脑区域中功能特化的神经元群的尖峰计时。为了检验这一假设，我们用光遗传学方法扰乱了大鼠内侧（MEC）和外侧（LEC）内嗅皮质的伽马尖峰时序，并分别发现了空间和物体学习任务的损伤。 MEC 和 LEC 分别通过高伽马频率节律和低伽马频率节律与海马齿状回同步，并以任务依赖性方式与颗粒细胞或苔藓细胞和 CA3 锥体细胞结合。伽马扰动破坏了目标神经元的学习诱导的组装组织。我们的研究结果表明，通路特异性伽马振荡在内嗅-海马回路中不同神经元亚群之间传递任务相关信息。我们假设区域间伽马时间尺度尖峰协调是神经元通讯的机制。