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bioRxiv · 10.1101/2025.09.15.676202

The orbitofrontal cortex forms a context-generalized spatial schema that preserves topology and distance

Abstract

Flexible and efficient navigation requires the brain to construct maps that are both topological, preserving the relationships between locations, and schematic, enabling generalization across environments. Although spatial maps in the hippocampus (HPC) and medial entorhinal cortex (MEC) have been extensively studied, they remap almost orthogonally across environments even during identical behaviors, raising the question of how animals maintain consistent navigation strategies across spatial contexts. Here, we identify a novel spatial map in the orbitofrontal cortex (OFC) that encodes navigational targets with distinct neural representations while preserving their topological order and relative distances by scaling to physical path lengths. Remarkably, OFC maps remained stable when animals performed the same navigation task across rooms and maze geometries, in stark contrast to the pronounced remapping observed in HPC and MEC. Moreover, OFC maps persisted after HPC or MEC lesions, demonstrating an independent spatial mapping system. These findings reveal a task-relevant topological schema in the OFC that uniquely supports flexible context-invariant navigation, expanding the brains spatial mapping repertoire beyond the hippocampal-entorhinal system.

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Basu, R., Mozaffarilegha, M., Bölükbası, I., Üstüner, C., Ito, H. T.. 2025-09-17. The orbitofrontal cortex forms a context-generalized spatial schema that preserves topology and distance. https://doi.org/10.1101/2025.09.15.676202

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