Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California, United States of America.
Department of Psychology, University of California, Berkeley, Berkeley, California, United States of America.
PLoS Biol. 2018 Mar 30;16(3):e2004274. doi: 10.1371/journal.pbio.2004274. eCollection 2018 Mar.
How do we rapidly process incoming streams of information in working memory, a cognitive mechanism central to human behavior? Dominant views of working memory focus on the prefrontal cortex (PFC), but human hippocampal recordings provide a neurophysiological signature distinct from the PFC. Are these regions independent, or do they interact in the service of working memory? We addressed this core issue in behavior by recording directly from frontotemporal sites in humans performing a visuospatial working memory task that operationalizes the types of identity and spatiotemporal information we encounter every day. Theta band oscillations drove bidirectional interactions between the PFC and medial temporal lobe (MTL; including the hippocampus). MTL theta oscillations directed the PFC preferentially during the processing of spatiotemporal information, while PFC theta oscillations directed the MTL for all types of information being processed in working memory. These findings reveal an MTL theta mechanism for processing space and time and a domain-general PFC theta mechanism, providing evidence that rapid, dynamic MTL-PFC interactions underlie working memory for everyday experiences.
我们如何在工作记忆中快速处理输入的信息流，工作记忆是人类行为的核心认知机制？工作记忆的主流观点集中在前额叶皮层（PFC），但人类海马体的记录提供了一种与 PFC 不同的神经生理学特征。这些区域是独立的，还是为了服务于工作记忆而相互作用？我们通过直接记录人类执行视觉空间工作记忆任务时的额颞区来解决这个核心问题，该任务将我们每天遇到的身份和时空信息类型进行了操作化处理。θ 波段振荡驱动 PFC 和内侧颞叶（MTL；包括海马体）之间的双向相互作用。在处理时空信息时，MTL 的θ 振荡优先引导 PFC，而 PFC 的θ 振荡则引导 MTL 处理工作记忆中所有类型的信息。这些发现揭示了一种 MTL 处理空间和时间的θ 机制，以及一种普遍的 PFC θ 机制，为日常经验的工作记忆提供了快速、动态的 MTL-PFC 相互作用的证据。
