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bioRxiv · 10.1101/2025.03.27.645795

Unraveling the mesoscale functional connectivity of the human primary visual cortex using high-resolution functional MRI.

Schmidt, M. E.·Aganj, I.·Stockmann, J.·Bilgic, B.·Chang, Y.·Hoge, W. S.·Kirilina, E.·Weiskopf, N.·Nasr, S.
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Abstract

Despite their importance for visual perception, functional connectivity between ocular dominance columns (ODCs)in the human primary visual cortex (V1) remains largely unknown. Using high- resolution functional MRI (fMRI), we localized ODCs and assessed their resting-state functional connectivity (rs-FC) in 12 human adults. Consistent with anatomical studies in animals, we found stronger rs-FC in the middle compared to deep and superficial cortical depths and selectively stronger rs- FC between ODCs with alike compared to unalike ocular polarity. Beyond what was known from animal models, and consistent with human perceptual biases, intra- and interhemispheric rs-FC was stronger in peripheral (compared to central) and in dorsal (compared to ventral) V1 subregions. Lastly, rs-FC patterns correlated with ODC maps, suggesting that ODC maps can be predicted from rs-FC patterns within V1. These results highlight the heterogeneity in rs-FC between ODCs across cortical depths and V1 subfields, underscoring their likely association with human perceptual features.

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Schmidt, M. E., Aganj, I., Stockmann, J., Bilgic, B., Chang, Y., Hoge, W. S., Kirilina, E., Weiskopf, N., Nasr, S.. 2025-04-01. Unraveling the mesoscale functional connectivity of the human primary visual cortex using high-resolution functional MRI.. https://doi.org/10.1101/2025.03.27.645795

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