NEURAL ENSEMBLE REFINEMENT IN THE PERIRHINAL CORTEX SUPPORTS SPATIAL LEARNING

The perirhinal cortex (PRH) plays a critical role in integrating sensory features with executive demands, yet its specific functional dynamics during active spatial learning remain poorly understood. This study utilizes a functional dissection approach to investigate the contribution of the PRH to spatial navigation and memory acquisition.

By employing longitudinal calcium imaging via miniature endoscopes, we monitored neural ensemble activity in mice performing a spatial learning task over several days of training. Our findings reveal that as mice progressed from novice to expert performance levels, pPRH neurons exhibited a significant, gradual increase in arm selectivity. This refinement of neural representations suggests that the pPRH undergoes task-dependent plasticity to encode spatial trajectories.

These results provide evidence that the pPRH is not merely a sensory relay but a dynamic component of the spatial learning circuit. By tracking these ensembles over time, this study offers deeper insights into the functional importance of the posterior perirhinal cortex in the consolidation of complex spatial memories.