Unraveling the mesoscale resting-state functional connectivity of ocular dominance columns in humans using high-resolution functional MRI.

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.