The precuneus has been identified as a key node within the DMN in functional connectivity analysis (Fransson and Marrelec, 2008). The precuneus has among the brain’s highest glucose metabolism consistent with a role requiring high levels of information processing relative to both orientation within and monitoring of external environment (Gusnard and Raichle, 2001). In a resting state study of chronic heroin users, left NAcc had reduced connectivity with left precuneus compared with controls (Ma et al., 2010). Our PPI results reveal dysfunction between these same structures. As expected, the FH− subjects in our sample had reduced connectivity during task, while FH+ increased coupling during active incentive processing, suggesting pre-existing dysfunctional connectivity between reward and DMN networks in our non-addicted, yet high-risk sample.
