挪威科学技术大学Christian F. Doeller、Joshua B. Julian团队合作取得最新进展。他们揭示人类海马结构的重新映射和重新排列预测情景相关的空间行为。该研究于2021年4月15日发表于国际一流学术期刊《自然-神经科学》。

人类参与者在两个不同的虚拟现实环境中学习了对象-位置关联，并随后在功能性MRI（fMRI）扫描期间测试了他们的记忆力。内嗅网格状表示显示两种情况之间的重新排列，并且在海马中观察到与重新映射一致的fMRI活动模式的同时变化。至关重要的是，在第三个模棱两可的情况下，海马-肠胃网络的逐次试验重映射和重新排列可以预测情景相关的行为。这些结果揭示了海马-肠内机制介导人类情境记忆，并表明在不确定性条件下，海马的形成在空间行为中起着关键作用。

据悉，为了指导空间行为，大脑必须检索与不同导航环境适当关联的记忆。情景记忆可能是由海马结构中的细胞集成介导的，这些细胞集成改变了它们对情景变化的响应，这些过程分别称为海马和内嗅皮层的重新映射和重新排列。但是，重新映射和重新排列是否指导情景相关的空间行为尚不清楚。

附：英文原文

Title: Remapping and realignment in the human hippocampal formation predict context-dependent spatial behavior

Author: Joshua B. Julian, Christian F. Doeller

Issue&Volume: 2021-04-15

Abstract: To guide spatial behavior, the brain must retrieve memories that are appropriately associated with different navigational contexts. Contextual memory might be mediated by cell ensembles in the hippocampal formation that alter their responses to changes in context, processes known as remapping and realignment in the hippocampus and entorhinal cortex, respectively. However, whether remapping and realignment guide context-dependent spatial behavior is unclear. To address this issue, human participants learned object–location associations within two distinct virtual reality environments and subsequently had their memory tested during functional MRI (fMRI) scanning. Entorhinal grid-like representations showed realignment between the two contexts, and coincident changes in fMRI activity patterns consistent with remapping were observed in the hippocampus. Critically, in a third ambiguous context, trial-by-trial remapping and realignment in the hippocampal–entorhinal network predicted context-dependent behavior. These results reveal the hippocampal–entorhinal mechanisms mediating human contextual memory and suggest that the hippocampal formation plays a key role in spatial behavior under uncertainty.

DOI: 10.1038/s41593-021-00835-3

Source: https://www.nature.com/articles/s41593-021-00835-3