Dorsal visual stream development improves symmetry of receptive field coverage and spatial attention.

The dorsal visual stream is a large retinotopic network in human visual cortex, involved in attentional and spatial aspects of vision critical for attending to, filtering, and interacting with the visual environment. The visual field maps which comprise the dorsal stream have not been characterized across development; a fundamental gap in human neuroscience given this pathway's role in critical childhood behaviors. Here, we designed a gamified task to retinotopically map the dorsal stream in both adults and children for the first time. We found that the dorsal representations of visual space undergo protracted development, increasing the area over which they pool information across the visual field. Children show an asymmetry in the way that receptive fields of each cerebral hemisphere tile visual space, with protracted development predominantly in the right hemisphere serving to balance coverage across the left and right sides of space. This divergence between the hemispheres' developmental trajectories has behavioral relevance, with individual variability in visuospatial attention biases correlating with receptive field properties from childhood into adulthood.