Differential Impact of Multiple Sensory Deprivation on Spatial-coding Cells in Medial Entorhinal Cortex

Spatial navigation depends on anchoring internal spatial maps to external environments, guided by sensory cues such as visual and tactile information. The Medial Entorhinal Cortex (MEC) is crucial for integrating these sensory inputs during the formation of spatial maps. While the responsiveness of many spatially modulated cells to visual stimuli is well-established, the role of tactile sensation in spatial representation is less understood. Rodents primarily gather tactile information through their whiskers, which provide essential spatial and textural details via whisking movements, potentially vital for constructing accurate spatial maps. In our study, we employed miniature two-photon microscopy to monitor neural activity in the MEC of freely moving male mice subjected to visual and tactile deprivation. We found that after spatial maps were established under visual guidance, head direction and border cells were disrupted by both light deprivation and whisker trimming, whereas grid and spatial cells were primarily dependent on visual input. In complete darkness with enriched tactile cues, however, all spatially modulated cell types could anchor their tuning to environmental tactile cues, and whisker trimming markedly impaired grid and spatial cell representations. A subset of neurons remained stable under combined deprivation, possibly relying on boundary-related tactile inputs from direct environmental contact. Additionally, we identified certain MEC neurons whose activity correlated with whisker movements, suggesting a potential role in integrating tactile information into spatial representations. These findings demonstrate that the MEC flexibly integrates multiple sensory inputs to sustain spatial coding and highlight a previously underappreciated contribution of tactile information to spatial navigation.