Ventromedial prefrontal cortex drives hippocampal theta oscillations induced by mismatch computations.
Ventromedial prefrontal cortex drives hippocampal theta oscillations induced by mismatch computations.
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DOI：
10.1016/j.neuroimage.2015.07.016
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发表时间：
2015-10-15
期刊：
影响因子：
5.7
通讯作者：
Dolan RJ
中科院分区：
文献类型：
--
作者：
Garrido MI;Barnes GR;Kumaran D;Maguire EA;Dolan RJ
探测环境变化是在不确定的世界中适应行为的基础。先前的研究表明，海马体通过匹配-不匹配检测器的实现来支持新颖性信号的产生，当传入的感官输入违反基于过去经验的预期时，该探测器会发出信号。虽然现有的工作强调了海马体的特殊贡献，但在这里，我们想知道哪些其他大脑结构也有助于匹配-不匹配检测。此外，我们利用脑磁图（MEG）的细粒度时间分辨率来研究错配计算是否在频谱上局限于theta范围，基于海马功能模型中该振荡范围的突出性。通过记录人类受试者执行包含匹配-不匹配新颖性条件的任务时的MEG活动，我们发现不匹配信号局限于θ波段，并在海马体和腹内侧前额叶皮层（vmPFC）中表达。有效的连通性分析（动态因果模型）表明，海马体和vmPFC在失配检测过程中作为一个功能电路工作。令人惊讶的是，我们的结果表明vmPFC在不匹配信号的产生和处理过程中驱动海马体。我们的发现为海马体- vmPFC回路参与新颖性处理提供了新的证据，这对关于vmPFC在记忆中的作用的新兴理论具有启示意义。失配检测涉及人类海马和腹内侧前额皮质。新奇的信号在频谱上局限于θ波段。腹内侧前额叶皮层驱动由错配引起的海马theta。
Detecting environmental change is fundamental for adaptive behavior in an uncertain world. Previous work indicates the hippocampus supports the generation of novelty signals via implementation of a match–mismatch detector that signals when an incoming sensory input violates expectations based on past experience. While existing work has emphasized the particular contribution of the hippocampus, here we ask which other brain structures also contribute to match–mismatch detection. Furthermore, we leverage the fine-grained temporal resolution of magnetoencephalography (MEG) to investigate whether mismatch computations are spectrally confined to the theta range, based on the prominence of this range of oscillations in models of hippocampal function. By recording MEG activity while human subjects perform a task that incorporates conditions of match–mismatch novelty we show that mismatch signals are confined to the theta band and are expressed in both the hippocampus and ventromedial prefrontal cortex (vmPFC). Effective connectivity analyses (dynamic causal modeling) show that the hippocampus and vmPFC work as a functional circuit during mismatch detection. Surprisingly, our results suggest that the vmPFC drives the hippocampus during the generation and processing of mismatch signals. Our findings provide new evidence that the hippocampal–vmPFC circuit is engaged during novelty processing, which has implications for emerging theories regarding the role of vmPFC in memory. Mismatch detection engages human hippocampus and ventromedial prefrontal cortex. Novelty signals are spectrally confined to the theta band. Ventromedial prefrontal cortex drives hippocampal theta induced by mismatches.