Fig. 3

A schematic overview of the study findings. In this study, we found that an early-life urban environment benefitted brain development in terms of the total, dorsolateral prefrontal cortex (DLPFC), and temporal gray matter volumes (GMVs), while an early-life rural environment benefitted the GMV of the medial prefrontal cortex (MPFC) in Brodmann area (BA) 8 and BA11. Regression analysis showed that having siblings is a protective environment factor for MPFC BA11 GMV; and higher mother’s education is a protective environment factor for total and DLPFC GMV. Mediation analysis showed that the total, DLPFC and temporal pole GMVs, which reflect the benefits of early-life urbanicity, could mediate the relationship between early-life urbanicity and cognitive function in adulthood