The primary goal of this study was to determine the developmental trajectories of the measures of the power of theta EROs obtained in the visual and auditory target detection tasks, and the trajectories of the correlations between them. The study focuses on elucidating gender, modality, and regional differences in these developmental trajectories. The trajectory of the correlations of power values provide a measure of the supraregional and supramodal characteristics of brain development of factors affecting theta ERO generation. In preliminary analyses, theta and delta band EROs in both total and evoked measures were examined. No significant differences in trajectories were found among these measures, so the analysis was restricted to the total power in the theta band in the three midline electrodes the interest of the simplicity of interpretation and consistency with prior studies (Jones et al., 2006a,b; Stige et al., 2007; Nanova et al., 2008). In subsequent studies, the developmental trajectories of the associations between genetic variants (SNPs) from a number of genes associated with neurophysiological factors and the measures of the power of theta EROs employed in this study will be determined using the same data set and similar methodologies.
