Center for Neural Science, New York University, New York, NY 10003, USA.
Center for Neural Science, New York University, New York, NY 10003, USA; Neuroscience Institute at the NYU Langone Medical Center, New York, NY 10003, USA.
Cell Rep. 2021 Aug 3;36(5):109497. doi: 10.1016/j.celrep.2021.109497.
Mouse hippocampus CA1 place-cell discharge typically encodes current location, but during slow gamma dominance (SG), when SG oscillations (30-50 Hz) dominate mid-frequency gamma oscillations (70-90 Hz) in CA1 local field potentials, CA1 discharge switches to represent distant recollected locations. We report that dentate spike type 2 (DS) events initiated by medial entorhinal cortex II (MECII)→ dentate gyrus (DG) inputs promote SG and change excitation-inhibition coordinated discharge in DG, CA3, and CA1, whereas type 1 (DS) events initiated by lateral entorhinal cortex II (LECII)→DG inputs do not. Just before SG, LECII-originating SG oscillations in DG and CA3-originating SG oscillations in CA1 phase and frequency synchronize at the DS peak when discharge within DG and CA3 increases to promote excitation-inhibition cofiring within and across the DG→CA3→CA1 pathway. This optimizes discharge for the 5-10 ms DG-to-CA1 neuro-transmission that SG initiates. DS properties identify extrahippocampal control of SG and a cortico-hippocampal mechanism that switches between memory-related modes of information processing.
小鼠海马 CA1 位置细胞放电通常编码当前位置，但在慢γ优势（SG）期间，当 SG 振荡（30-50 Hz）在 CA1 局部场电位中主导中频γ振荡（70-90 Hz）时，CA1 放电切换以代表遥远的回忆位置。我们报告说，由内侧缰状核 II（MECII）到齿状回（DG）输入引发的齿状尖峰类型 2（DS）事件促进了 SG，并改变了 DG、CA3 和 CA1 中的兴奋抑制协调放电，而由外侧缰状核 II（LECII）到 DG 输入引发的类型 1（DS）事件则不会。就在 SG 之前，当 DG 和 CA3 中的 LECII 起源的 SG 振荡在 DS 峰值时相位和频率同步时，DG 和 CA3 中的放电增加，以促进 DG→CA3→CA1 通路中的兴奋抑制共发射，DG 中的 SG 振荡和 CA1 中的 SG 振荡起源于 CA1。这优化了 SG 启动的 5-10 ms 的 DG 到 CA1 的神经传递。DS 属性确定了海马外的 SG 控制和一种皮质-海马机制，该机制在记忆相关的信息处理模式之间切换。
