Environment geometry alters subiculum boundary vector cell receptive fields in adulthood and early development

• Published in: Nature communications 2024-02, Vol.15 (1), p.982-17, Article 982
• Main Authors: Muessig, Laurenz, Ribeiro Rodrigues, Fabio, Bjerknes, Tale L., Towse, Benjamin W., Barry, Caswell, Burgess, Neil, Moser, Edvard I., Moser, May-Britt, Cacucci, Francesca, Wills, Thomas J.
• Format: Article
• Language: English
• Subjects: 631/378/1595/1554; 631/378/1595/3922; 631/378/2629/2630; 64/86; 9/30; Boundaries; Circles (geometry); Cortex (entorhinal); Displacement; Geometry; Hippocampus; Humanities and Social Sciences; multidisciplinary; Navigation behavior; Neurons; Science; Science (multidisciplinary); Subiculum
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-45098-1

Boundaries to movement form a specific class of landmark information used for navigation: Boundary Vector Cells (BVCs) are neurons which encode an animal’s location as a vector displacement from boundaries. Here we characterise the prevalence and spatial tuning of subiculum BVCs in adult and developing male rats, and investigate the relationship between BVC spatial firing and boundary geometry. BVC directional tunings align with environment walls in squares, but are uniformly distributed in circles, demonstrating that environmental geometry alters BVC receptive fields. Inserted barriers uncover both excitatory and inhibitory components to BVC receptive fields, demonstrating that inhibitory inputs contribute to BVC field formation. During post-natal development, subiculum BVCs mature slowly, contrasting with the earlier maturation of boundary-responsive cells in upstream Entorhinal Cortex. However, Subiculum and Entorhinal BVC receptive fields are altered by boundary geometry as early as tested, suggesting this is an inherent feature of the hippocampal representation of space. How neural responses to boundaries develop in the subiculum remains unknown. Here authors show that the receptive fields of Boundary Vector Cells (neurons signalling vector displacement to boundaries) are altered by environment geometry, with directional tunings aligning with square arena walls, including during development.