The trajectories of intermodal correlations and of ERO power development suggest that there is a developmental transition span centered at age 18 and ranging from ages 16 to 21, marked by a pattern of divergent development in the auditory and visual systems, particularly in females. As discussed above (see section 3.2.2 and Figure 2), there is a decrease in intermodal power correlation from ages 15 to 18, followed by recovery beyond previous levels from ages 18 to 25, particularly large in females. All but one of the twelve gender specific differences between minimum values and values at age 25 which are significant at the p < 10−6 level occur in intermodal correlations. Since intramodal power correlations have no such decrease and recovery pattern, it can be supposed that there is a transition between distinct regimes in supramodal development not found in supraregional development, which accounts for the divergence between auditory and visual development. The study by Walz et al. (2013) found that common brain regions in the same individuals were activated in independent auditory and visual oddball tasks. However, the
