Pecirno, S. A. | Search bioRxiv

bioRxiv2025

Change-resistance distinguishes the representational geometries of human spatial memory and mouse CA1 in deformed environments

Prior work has highlighted qualitative similarities between the neural instantiations of cognitive maps in rodents and memory-guided navigation in humans, suggesting a conservation of representational structure across species. Yet evidence of cross-species differences in neural coding continues to mount. Our ability to reconcile these similarities and differences has been inherently limited by the qualitative nature of our cross-species comparisons. To overcome this limitation, here we combine recent technical and theoretical advances to characterize the representational geometry of human spatial memory during a diverse set of environmental deformations and compare this geometry to that of mouse CA1. Across three untethered immersive virtual reality experiments (n > 100 participants per experiment), we find that deformations induce compounding local distortions in human spatial memory. These distortions yield a representational geometry which closely resembles a change-resistant version of that of mouse hippocampal CA1 during analogous deformations. The geometries of mouse CA1 subpopulations with higher firing rates, spatial tuning stability, and spatial tuning specificity all better resembled that of human spatial memory. The precision, but not accuracy, of human spatial memory also modulated cross-species resemblance. The local impact of deformations scaled up when humans navigated a larger environment, preserving representational geometry and cross-species resemblance. Neither geometry nor cross-species resemblance depended on the human visual advantage during retrieval. Together, these results establish a common cross-species resemblance in the representational geometry of mouse CA1 and human spatial memory during environmental deformations, with a notable difference in the resistance to change between these assays.

neuroscience↗

bioRxiv2024

Idiosyncratic navigation determines mouse CA1 representational structure in a multicompartment environment

Predictive theories of cognitive mapping propose that these representations encode the predictive relationships among contents as experienced by the navigator. One hallmark of these theories is that representational structure in complex environments can be predicted from the behavioral history of the navigator. Here, we image neural activity in hippocampal CA1 as initially naive mice repeatedly navigate a multicompartment environment to test whether representational structure in this subregion is consistent with these predictions. We find that different mice instantiate different patterns of remapping across identically shaped compartments. Within mouse, compartments with more similar predictive navigational histories on a particular spatiotemporal scale are represented more similarly, accounting for these individual differences. Manipulating navigational options induces reorganization of the CA1 structure which specifically resembles the new predictive navigational structure on this scale. Through computational modeling we show that a combination of predictive encoding and geometrically structured inputs can uniquely account for this pattern of results. Together, these results demonstrate that the structure of CA1 representations in complex environments can be predicted from the behavioral history of the navigator, consistent with predictive theories of cognitive mapping.

neuroscience↗