The Development of Receptive Fields and Functional Connectivity in the Human Dorsal Stream

Abstract

The dorsal stream is a vision processing pathway in the occipital and parietal cortex responsible for visually guided action, motion processing, visuospatial attention, and working memory. How receptive fields in the human dorsal stream change across development is unknown. Here we use fMRI to model population receptive fields (pRFs) for voxels on the cortical surface and measure how they differ between children aged 5-12 and adults aged 22-28. We were able to compare pRFs between 6 occipito-parietal retinotopic maps across development: V1, V2, V3, V3A/B, IPS0, and IPS1. We find that dorsal stream pRFs increase in size, eccentricity, and visual field coverage across development, with the largest changes occurring in IPS1. While we were not able to consistently define retinotopic maps beyond IPS1, we find a significant increase in retinotopically driven voxels across development in probabilistic maps of dorsal stream regions extending to IPS5 and SPL1, with the largest increase in IPS2. Finally, we found significant increases in functional connectivity between dorsal stream regions and their contralateral word-selective regions in the occipito-temporal sulcus. These findings suggest that the neural machinery for visuospatial processing becomes more attuned to the periphery and more functionally connected to word processing areas, which is consistent with the development of visuospatial behavior and reading in humans.