Functional connectivity analysis with the dorsal striatum (caudate) as the seed region revealed a similar pattern whereby G-allele carriers showed stronger negative connectivity with the insula, OFC, paracingulate gyrus, and subcallosal cortex. These findings are contrary to the initial hypothesis that differences in fronto-striatal functional connectivity patterns across groups would be unique to the ventral striatum (signaling reward-driven drinking), and not present for the dorsal striatum (signaling habit-driven drinking). In fact, these results suggest that this candidate gene contributes to negative correlations in both ventral and dorsal fronto-striatal functional connectivity during alcohol cues processing. In other words, there was no evidence for dissociation of the functional connectivity patterns across striatal subregions moderated by this polymorphism.
