Asumbisa, K. | Search bioRxiv

bioRxiv2026

Reproducible and predictable reorganization of place fields driven by grid subfield rate changes

Understanding how the brain constructs stable yet flexible maps of space remains a central challenge in neuroscience. Place cells in the hippocampus fire at specific locations in a given environment, but reorganize completely upon introduction to another environment in a process called remapping. The medial entorhinal cortex (MEC) provides a major cortical input to the hippocampus, and the spatially periodic firing patterns of its grid cells are thought to contribute to place field formation. We previously showed that chemogenetic depolarization of MEC layer II stellate cells selectively altered firing rates within individual grid cell subfields, impaired spatial memory, and induced a form of reversible place cell remapping that we called artificial remapping. However, it remains unclear whether artificial remapping reflects a reproducible and stable mapping from entorhinal inputs to place cell outputs or a random reorganization of place fields. To explore the transfer of information between MEC and hippocampus, we repeated this chemogenetic manipulation on consecutive days and found that stimulating the same stellate cells produced similar changes in both grid subfield rates and place field locations. Using both experimental and simulated data, we show that baseline place cell activity patterns could be used to predict place field locations following the manipulation. These findings provide direct evidence for consistent input-output relationships in the entorhinal-hippocampal system and point to a central role for grid subfield rate changes in the reorganization of hippocampal spatial representations.

neuroscience↗

bioRxiv2022

Flexible cue anchoring strategies enable stable head direction coding in both sighted and blind animals

Vision plays a crucial role in instructing the brains spatial navigation systems. However, little is known about how vision loss affects the neuronal encoding of spatial information. Here, recording from head direction (HD) cells in the anterior dorsal nucleus of the thalamus in mice, we find stable and robust HD tuning in blind animals. In contrast, placing sighted animals in darkness significantly impairs HD cell tuning. We find that blind mice use olfactory cues to maintain stable HD tuning and that prior visual experience leads to refined HD cell tuning in blind adult mice compared to congenitally blind animals. Finally, in the absence of both visual and olfactory cues, the HD attractor network remains intact but the preferred firing direction of HD cells continuously drifts over time. We thus demonstrate remarkable flexibility in how the brain uses diverse sensory information to generate a stable directional representation of space. HighlightsO_LIHead direction (HD) cell tuning in ADn is robust in blind animals, but unstable in sighted animals placed in the dark C_LIO_LIBlind mice use olfaction to stabilize HD cell tuning C_LIO_LIPrior visual experience leads to refined HD cell tuning in blind adult mice C_LIO_LIIn the absence of both vision and olfaction, the HD attractor network in ADn remains intact but the preferred firing direction of HD cells continuously drifts C_LI

neuroscience↗