cognitive processing and IQ (Comings et al., 2003; Dick et al., 2007; Gosso et al., 2007), and has been implicated in alcohol and drug dependence (Luo et al., 2005; Wang et al., 2004), and, most recently, in externalizing disorders (Dick et al., 2008). While there is yet no study of pleiotropic effects (i.e. shared genetic influences by CHRM2 on both alcoholism and P3-related delta and theta activity), these findings demonstrate the promise of event-related delta and theta as endophenotypes of alcoholism. Left unanswered, however, is whether this promise extends to other disorders that compose the externalizing psychopathology spectrum.
