with externalizing phenotypes and illustrate the promise of this approach for identifying heritable neural mechanisms associated with genetic predispositions for externalizing. An important next step in this line of research is to examine the neurobiological correlates of the externalizing PS. Research that aims to characterize the influences of genetic variations on brain structures and function has grown exponentially over the past several years, and yielded greater insight into the heritability of neurobiological risk factors for psychopathology, including emerging neurogenetics research on externalizing disorders (e.g., Heitzeg et al., 2014; Karoly, et al., 2013; Shehzad et al., 2012). To our knowledge, no research to date has examined whether the externalizing PS relates to neurobiological function or structure – potentially crucial pathways by which genes create vulnerability for externalizing disorders.
