Investigating Venous Interference in Population Receptive Field Estimation using High-resolution 3D-EPI at 7T

Motivation: Understanding that what causes the variation in population reception field (pRF) size with identical eccentricities is important for improving the accuracy of pRF estimation and purifying the functional signal in retinotopic mapping. Goal(s): To investigate whether penetrating veins in visual cortex contribute to local overestimation of pRF size. Approach: We used high-resolution quantitative susceptibility mapping acquired through 3D-EPI sequences for venous quantification and employed cortical unfolding to analyze the relationship between venous locations and large pRF estimates. Results: Our results initially demonstrated colocalization between pRF size and penetrating veins, although in some regions, mismatches between the two patterns were observed due to misregistration. Impact: This study provides new insights into the role of venous interference in pRF estimation, with the potential to address longstanding challenges in understanding the venous structure of visual cortex and improving the accuracy of retinotopic mapping.