To characterize the relationship between connection length and the change in correlation strength over development, we split all 561 possible connections into 4 groups based on vector distance. Since using vector distance as an approximate for connectional distance is much more inconsistent when comparing ROIs across the midline, only intrahemispheric connections or connections to midline structures (i.e., within 5 mm of the midline) were examined. These connections were then sorted by connection length and plotted on a graph where the x-axis corresponds to the child correlation strengths and the y-axis corresponds to the adult correlation strengths (Figure 5 and Figure S2). On both the graphs (Figure 5) and the cortical surfaces (Figure S2), the color of the lines denotes the strength of correlation. Significant differences seen in Figure 5 and Figure S2 were obtained via direct comparison between children (the youngest 60 children out of 210 total subjects; age 7.01–9.67; average age 8.48) and adults (the oldest 60 adults out of 210 total subjects; age 22.47–31.39; average age 25.48). Two-sample two-tailed t-tests (assuming unequal variance; p≤0.05) were performed on all
