Comparing retinotopic maps of children and adults reveals a late-stage change in how V1 samples the visual field

Adult visual performance differs with angular location -it is better for stimuli along the horizontal than vertical, and lower than upper vertical meridian of the visual field. These perceptual asymmetries are paralleled by asymmetries in cortical surface area in primary visual cortex (V1). Children, unlike adults, have similar visual performance at the lower and upper vertical meridian. Do children have similar V1 surface area representing the upper and lower vertical meridian? Using MRI, we measure the surface area of retinotopic maps (V1-V3) in children and adults. Many features of the maps are similar between groups, including greater V1 surface area for the horizontal than vertical meridian. However, unlike adults, children have a similar amount of V1 surface area representing the lower and upper vertical meridian. These data reveal a late-stage change in V1 organization that may relate to the emergence of the visual performance asymmetry along the vertical meridian by adulthood. Many properties of human primary visual cortex (V1) are 'adult-like' by childhood. Here, using fMRI, the authors show that V1 of children and adults differentially sample the visual field, indicating a late-stage change in cortical organization.

Automated summary

Adults have better visual performance for stimuli along the horizontal than vertical and lower than upper vertical meridian, which is paralleled by cortical surface area asymmetries in V1. However, children have similar visual performance for the lower and upper vertical meridian, and similar V1 surface area representing them. This suggests a late-stage change in V1 organization that corresponds to the emergence of visual performance asymmetry in adults along the vertical meridian. The study also shows that many features of V1 are adult-like in children, indicating a developmental change in cortical organization.