Graduate Program in Neuroscience, University of Minnesota Twin Cities, Minneapolis, MN, USA.
Department of Neuroscience, University of Minnesota Twin Cities, Minneapolis, MN, USA.
Neurobiol Learn Mem. 2020 May;171:107215. doi: 10.1016/j.nlm.2020.107215. Epub 2020 Apr 8.
Dorsomedial prefrontal cortex (dmPFC) and hippocampus (HPC) are thought to play complementary roles in a spatial working memory and decision-making network, where spatial information from HPC informs representations in dmPFC, and contextual information from dmPFC biases how HPC recalls that information. We recorded simultaneously from neural ensembles in rodent dmPFC and HPC as rats performed a rule-switching task, and found that ensembles in dmPFC and HPC simultaneously encoded task contingencies and other time-varying information. While ensembles in HPC transitioned to represent new contingencies at the same time as rats updated their strategies to be consistent with the new contingency, dmPFC ensembles transitioned earlier. Neural representations of other time-varying information also changed faster in dmPFC than in HPC. Our results suggest that HPC and dmPFC represent contingencies while simultaneously representing other information which changes over time, and that this contextual information is integrated into hippocampal representations more slowly than in dmPFC.
背内侧前额叶皮层（dmPFC）和海马体（HPC）被认为在空间工作记忆和决策网络中发挥着互补作用，其中来自 HPC 的空间信息为 dmPFC 中的表示提供信息，而来自 dmPFC 的上下文信息则影响 HPC 回忆该信息的方式。当大鼠执行规则转换任务时，我们同时记录了啮齿动物 dmPFC 和 HPC 中的神经集合的活动，发现 dmPFC 和 HPC 中的集合同时编码了任务的偶然性和其他时变信息。虽然 HPC 中的集合在大鼠更新策略以适应新的偶然性的同时开始代表新的偶然性，但 dmPFC 中的集合更早地转变。dmPFC 中的其他时变信息的神经表示也比 HPC 中变化得更快。我们的研究结果表明，HPC 和 dmPFC 在同时代表其他随时间变化的信息的同时代表偶然性，并且这种上下文信息比 dmPFC 中的信息更缓慢地整合到海马体的表示中。
