近日，美国约翰霍普金斯大学教授James J. Knierim及其课题组开发出异源性与自源性空间线索调控位置细胞θ相位多重编码。相关论文于2025年8月26日发表于国际顶尖学术期刊《自然—神经科学》杂志上。

结合虚拟现实、电生理学和计算建模，该课题组研究人员为这种功能复用的相位代码提供了实验证据，并描述了不同的空间输入如何控制其表现。具体来说，当大鼠不断学习外部地标（异体）线索和自我运动（异体）线索之间的新联系时，阶段“进动”保持完整，允许它们继续预测未来的位置。相反，“处理”阶段被减弱，与在早期θ波阶段编码的假定作用相匹配。这种多路复用相位码可以用作亚秒尺度上交替进行不同计算的一般电路逻辑。

研究人员表示，θ波振荡被认为是海马计算的一个时间支架，它组织了被称为位置细胞的空间调谐细胞的活动。θ的后期阶段通过阶段“进动”支持前瞻性空间表征。相比之下，一些研究假设，θ的早期阶段可能通过阶段“处理”和新关联的编码来支持回顾性空间表征。

附：英文原文

Title: Allothetic and idiothetic spatial cues control the multiplexed theta phase coding of place cells

Author: Sueoka, Yotaro, Jayakumar, Ravikrishnan P., Madhav, Manu S., Savelli, Francesco, Cowan, Noah J., Knierim, James J.

Issue&Volume: 2025-08-26

Abstract: Theta oscillation is considered a temporal scaffold for hippocampal computations that organizes the activity of spatially tuned cells known as place cells. Late phases of theta support prospective spatial representation via phase ‘precession’. In contrast, some studies have hypothesized that early phases of theta may subserve both retrospective spatial representation via phase ‘procession’ and the encoding of new associations. Here, combining virtual reality, electrophysiology and computational modeling, we provide experimental evidence for such a functionally multiplexed phase code and describe how distinct spatial inputs control its manifestation. Specifically, when rats continuously learned new associations between external landmark (allothetic) cues and self-motion (idiothetic) cues, phase ‘precession’ remained intact, allowing continuous prediction of future positions. Conversely, phase ‘procession’ was diminished, matching the putative role in encoding at the early theta phase. This multiplexed phase code may serve as a general circuit logic for alternating different computations at a sub-second scale.

DOI: 10.1038/s41593-025-02038-6

Source: https://www.nature.com/articles/s41593-025-02038-6