Climer Jason R, Davoudi Heydar, Oh Jun Young, Dombeck Daniel A
Department of Neurobiology, Northwestern University, Evanston, IL, USA.
Department of Molecular and Integrative Physiology, University of Illinois, Champaign, IL, USA.
Nature. 2025 Jul 23. doi: 10.1038/s41586-025-09245-y.
Experiments that track hippocampal place cells in mice navigating the same real environment have found significant changes in neural representations over a period of days. However, whether such 'representational drift' serves an intrinsic function, such as distinguishing similar experiences that occur at different times, or is instead observed due to subtle differences in the sensory environment or behaviour, remains unresolved. Here we used the experimental control offered by a multisensory virtual reality system to determine that differences in sensory environment or behaviour do not detectably change drift rate. We also found that the excitability of individual place cells was most predictive of their representational drift over subsequent days, with more excitable cells exhibiting less drift. These findings establish that representational drift occurs in mice even with highly reproducible environments and behaviour and highlight neuronal excitability as a key factor of long-term representational stability.
在追踪小鼠在同一真实环境中导航时海马体位置细胞的实验中，研究人员发现在数天时间里神经表征发生了显著变化。然而，这种“表征漂移”是具有内在功能，比如区分在不同时间发生的相似经历，还是由于感官环境或行为的细微差异而被观察到，这一问题仍未得到解决。在这里，我们利用多感官虚拟现实系统提供的实验控制来确定，感官环境或行为的差异不会显著改变漂移率。我们还发现，单个位置细胞的兴奋性最能预测其在随后几天的表征漂移，兴奋性较高的细胞表现出的漂移较少。这些发现表明，即使在高度可重复的环境和行为下，小鼠体内也会发生表征漂移，并突出了神经元兴奋性是长期表征稳定性的关键因素。
