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Mapping Adolescent Brain Change 67Figure 3-5 DFC age-effect statistical maps (left, right, and top views) showing changes inDFC between childhood and adolescence (A) and between adolescence and adulthood (B).Anatomically, the central sulcus (CS), Sylvian fissure (SF), and interhemispheric fissure(IF) are highlighted. In both images, shades of green to yellow represent positive Pearson’scorrelation coefficients (increased DFC or brain growth) and shades of blue, purple, andpink represent negative Pearson’s correlation coefficients (decreased DFC or shrinkage)according to the color bar on the right (range of Pearson correlation coefficients from –1to +1). Regions shown in red correspond to correlation coefficients that have significantpositive age effects at a threshold of p = 0.05 (brain growth), and regions shown in whitecorrespond to significant negative age effects at a threshold of p = 0.05 (brain shrinkage).The images on the bottom (C) display a statistical map of the Fisher’s Z transformation ofthe difference between Pearson correlation coefficients for the child-to-adolescent and theadolescent-to-adult contrasts (see color bar on far right representing Z-scores from –5 to+5). Shades of green to yellow represent regions where the age effects are more significantin the adolescent-to-adult contrast (middle image) than in the child-to-adolescentcontrast (left image). Highlighted in red are the regions where the difference betweenPearson correlation coefficients is statistically significant (p = 0.05). Shades of blue, purple,and pink represent regions where the age effects are more significant in the child-toadolescentcontrast than the adolescent-to-adult contrast. Highlighted in white are regionswhere these effects are significant at a threshold of p = 0.05. Note the sign of the differencesbetween contrasts is opposite to that in the difference map for the gray matter densitycontrasts because of the inverse relationship between gray matter density (negativeeffects) and late brain growth (positive effects). See color insert. (Sowell et al., 2001b.)