Compared to the younger age group, the older subjects showed relatively higher P3 amplitudes at frontal regions, while the younger group showed relatively higher P3 amplitudes at parietal and occipital regions. The anterior-posterior modulation (“frontalization”) during brain development has been well-documented in the EEG literature. Maturational patterns of EEG activity follow grey matter reduction during development, as there is a redistribution of relative EEG power as a function of age with posterior regions maturing earlier than anterior regions (cf. Segalowitz et al., 2010). During development, theta-alpha maturation occurs first in occipital regions and then progresses gradually to frontal regions (Matousek and Petersen, 1973b; Gasser et al., 1988a; Dustman et al., 1999). Yordanova and Kolev (1996) demonstrated similar age effects in EROs by demonstrating that adults showed ERO alpha maxima at mid-central regions in contrast to the parietal maxima in children, reflecting perhaps a gradual “frontalization” with growth (cf. Segalowitz et al., 2010). These studies support our finding related to anterior-posterior differences in younger and older groups.
