High-resolution fMRI mapping of ocular dominance columns at laminar level in cat visual cortex

Motivation: Most fMRI column studies don’t consider the potentially different laminar responses along the cortical depth. Goal(s): In this work, we demonstrate the feasibility of mapping ocular dominance columns (ODCs) at multiple cortical depths in the cat visual cortex using CBV-weighted fMRI. Approach: To enable monocular input to either eye of a cat, we customized a cat goggle that can avoid light leakage and switch eyes easily. Results: By employing mesoscopic fMRI at ultrahigh magnetic field (9.4 Tesla), we observed relatively irregular ODC stripes in the cat visual cortex with a large width and length variation, extending across the cortex with varying response strength. Impact: The successful ODC mapping across multiple cortical depths using high-resolution fMRI in the cat brain enables investigation of layer-specific neural circuits and column mapping on the effect of combined stimulus dimensions at both the thalamocortical and intracortical level.