Although this type of biometric moderation modeling has not been applied to the study of P300 amplitude, it has been applied to the study of other characteristics, and findings have been reported indicating that effects like those depicted in Figures 1b and 1c are reasonable. For instance, Button, Lau, Maughan, and Elay (2008) found that the genetic contribution to adolescent externalizing behavior was increased with environmental adversity (punitive parenting style), a result that is consistent with a diathesis-stress model for the development of externalizing. In a study of adolescent depression, Feinberg, Button, Neiderhiser, Reiss, and Hetherington (2007) reported that with increasing parental negativity, the genetic influence was constant but the nonshared environmental effect on depression increased, a finding similar to that displayed in Figure 1c. Studies such as these demonstrate how traditional heritability estimates may obscure dynamic G-E interplay. They also point to the potential power of moderation models to characterize dynamic G-E interplay among P3AR and AAU, phenomena that naturally covary, to elucidate the mechanisms by which AAU impacts adolescent brain development.
