ERO theta power during a monetary gambling task has been reported to be reduced while processing monetary loss and gain in both alcoholics and their high risk offspring (Kamarajan et al., 2012; Kamarajan et al., 2015a), and the findings were interpreted as reward processing deficits in these groups. There is evidence to show that neural oscillations during reward processing underlie brain reward regions and/or circuits. For example, in a combined study of time-frequency ERO measure and fMRI data in human participants, (Mas-Herrero et al., 2015) reported that oscillatory activity elicited by monetary gains was associated with fronto-striatal-hippocampal reward network identified by the fMRI activity. Studies using implanted depth electrodes in rats have reported that neural oscillations were modulated by anticipation and delivery of reward (van der Meer and Redish, 2009; Kalenscher et al., 2010; Malhotra, 2014). Animal studies have also reported that genetic ablation of G-protein-regulated inward-rectifier potassium channel 2 (GIRK2, a protein encoded by KCNJ6 gene), promotes adaptations in the mesolimbic dopaminergic system (Cooper et al., 2012; Kotecki, 2015), a mechanism which is related to brain reward network and
