Neural and behavioural state switching during hippocampal dentate spikes.
Neural and behavioural state switching during hippocampal dentate spikes.
复制标题
海马齿状尖峰期间的神经和行为状态切换。
DOI：
10.1038/s41586-024-07192-8
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发表时间：
2024
期刊：
影响因子：
64.8
通讯作者：
Soltesz,Ivan
中科院分区：
文献类型：
--
作者：
Farrell,JordanS;Hwaun,Ernie;Dudok,Barna;Soltesz,Ivan
不同的大脑和行为状态与有组织的神经种群动态有关，这些动态被认为具有特定的认知功能。例如，记忆重放事件发生在被称为海马体尖波涟漪的同步群体事件期间，而小鼠处于离线行为状态，从而启用了记忆巩固和规划等认知机制。但在这种行为状态下，大脑如何与外部世界重新接触，并允许获取当前的感觉信息或促进新记忆的形成？在这里，我们发现，海马齿状峰，一个未被研究的群体事件，经常发生在尖锐的波纹之间，可能是这种机制的基础。我们发现，齿状棘波与全脑放电频率明显升高有关，这主要是在更高级别的网络中观察到的，并与短暂的觉醒时期相关联。与伴随尖锐波纹的记忆重播不同，齿状棘波期间的海马区位置编码与老鼠当前的空间位置一致。此外，在齿状棘波期间抑制神经活动会扰乱联想记忆的形成。因此，齿状棘波代表了一种不同的大脑状态，并在非运动行为中支持记忆，将认知过程的范围扩展到经典的脱机功能之外。
Distinct brain and behavioural states are associated with organized neural population dynamics that are thought to serve specific cognitive functions, –. Memory replay events, for example, occur during synchronous population events called sharp-wave ripples in the hippocampus while mice are in an ‘offline’ behavioural state, enabling cognitive mechanisms such as memory consolidation and planning, , , , , , –. But how does the brain re-engage with the external world during this behavioural state and permit access to current sensory information or promote new memory formation? Here we found that the hippocampal dentate spike, an understudied population event that frequently occurs between sharp-wave ripples, may underlie such a mechanism. We show that dentate spikes are associated with distinctly elevated brain-wide firing rates, primarily observed in higher order networks, and couple to brief periods of arousal. Hippocampal place coding during dentate spikes aligns to the mouse’s current spatial location, unlike the memory replay accompanying sharp-wave ripples. Furthermore, inhibiting neural activity during dentate spikes disrupts associative memory formation. Thus, dentate spikes represent a distinct brain state and support memory during non-locomotor behaviour, extending the repertoire of cognitive processes beyond the classical offline functions.