Title: Cortical recycling in high-level visual cortex during childhood

Human ventral temporal cortex (VTC) contains category-selective regions that respond 16 preferentially to ecologically-relevant categories such as faces1, bodies2, places3, and words4 and 17 are causally involved in the perception of these categories5–7. However, it is unknown how these 18 regions develop during childhood. Here we used functional MRI and images from many 19 categories to measure longitudinal development of category-selectivity in individual school-age 20 children over the course of 5 years. We show that from young childhood to the teens, faceand 21 word-selective regions in VTC expand and increase in their respective category-selectivity, but 22 limb-selective regions in VTC shrink and lose their preference for limbs. Critically, as a child 23 develops, increases in their faceand word-selectivity are directly linked to decreases in limb24 selectivity. These data show that during childhood limb-selectivity in VTC is repurposed into 25 wordand face-selectivity providing the first empirical evidence for cortical recycling8 during 26 childhood development. These results suggest a rethinking of prevailing hypotheses that cortical 27 development involves sculpting of new representations upon general-purpose cortex9,10. Instead, 28 they suggest a new hypothesis that during development VTC representations adjust to changes in 29 the salience and social relevance of visual inputs11, which has important implications for both 30 typical and atypical brain development. 31