Department of Neurobiology, Stanford University, Stanford, CA, USA.
Nat Neurosci. 2021 May;24(5):705-714. doi: 10.1038/s41593-021-00816-6. Epub 2021 Mar 22.
The hippocampus contains neural representations capable of supporting declarative memory. Hippocampal place cells are one such representation, firing in one or few locations in a given environment. Between environments, place cell firing fields remap (turning on/off or moving to a new location) to provide a population-wide code for distinct contexts. However, the manner by which contextual features combine to drive hippocampal remapping remains a matter of debate. Using large-scale in vivo two-photon intracellular calcium recordings in mice during virtual navigation, we show that remapping in the hippocampal region CA1 is driven by prior experience regarding the frequency of certain contexts and that remapping approximates an optimal estimate of the identity of the current context. A simple associative-learning mechanism reproduces these results. Together, our findings demonstrate that place cell remapping allows an animal to simultaneously identify its physical location and optimally estimate the identity of the environment.
海马体包含能够支持陈述性记忆的神经表示。海马体位置细胞就是这样一种表示，在给定环境中在一个或少数几个位置发射。在环境之间，位置细胞发射场重新映射（打开/关闭或移动到新位置），以提供用于不同上下文的广泛的群体代码。然而，上下文特征组合以驱动海马体重新映射的方式仍然存在争议。在虚拟导航过程中，我们使用在小鼠中进行的大规模体内双光子细胞内钙记录，表明 CA1 海马区的重新映射是由关于某些上下文频率的先前经验驱动的，并且重新映射近似于当前上下文身份的最佳估计。一个简单的联想学习机制再现了这些结果。总之，我们的发现表明，位置细胞重新映射使动物能够同时识别其物理位置并最佳估计环境的身份。
