The major finding of the current study is that genotypic variations in the KCNJ6 SNP (rs702859) influenced both magnitude and topography of ERO theta power with the minor allele (G) contributing to higher theta power (GG > AG > AA) at central and parietal regions (see Figs. 3 and 4). Previous studies have suggested that higher theta power during task conditions indicate efficient cognitive processing (Klimesch, 1999; Basar et al., 2001b). For example, individuals with and/or at risk for AUD have been shown to have lower theta power in several cognitive paradigms, reflecting deficient neurocognitive functioning in these individuals (Kamarajan et al., 2004; Jones et al., 2006b; Kamarajan et al., 2006; Rangaswamy et al., 2007; Kamarajan et al., 2012; Kamarajan et al., 2015a; Pandey et al., 2016). Therefore, the current findings of higher theta power during reward processing in the carriers of minor alleles may indicate that they have more efficient cognitive processing. Future studies will be needed to determine whether carrying the minor allele perhaps confers a ‘protective’ factor.
