We used a MID task to probe the reward network of young adults hypothesizing that reward system connectivity would differ based on familial risk for substance abuse and these differences would mediate the relationship between sensation-seeking personality and drinking behavior. This is the first study to demonstrate differences in anticipatory reward-related functional connectivity based on family history using psychophysiological interaction (PPI) analyses seeded from the NAcc. We found that left NAcc connectivity with SSMA and right precuneus mediated the relationship between sensation-seeking and alcohol consumption in high-risk youth (FH+). Accumbens functional connectivity with the SSMA and precuneus, as well as other frontal and parietal regions including the paracentral lobule and sensorimotor areas, was not only significantly different by group, but these couplings changed in opposite directions in response to the reward task. FH− subjects demonstrated reductions in coupling between these structures during incentive anticipation, while FH+ increased coupling, potentially representing a neurobiological difference related to vulnerability.
