Neural Correlates of Substance Abuse: Reduced Functional Connectivity Between Areas Underlying Reward and Cognitive Control

Human Brain Mapping (Impact Factor: 5.97). 09/2014; 35(9). DOI: 10.1002/hbm.22474
Source: PubMed


Substance use disorders (SUD) have been associated with dysfunction in reward processing, habit formation, and cognitive-behavioral control. Accordingly, neurocircuitry models of addiction highlight roles for nucleus accumbens, dorsal striatum, and prefrontal/anterior cingulate cortex. However, the precise nature of the disrupted interactions between these brain regions in SUD, and the psychological correlates thereof, remain unclear. Here we used magnetic resonance imaging to measure rest-state functional connectivity of three key striatal nuclei (nucleus accumbens, dorsal caudate, and dorsal putamen) in a sample of 40 adult male prison inmates (n = 22 diagnosed with SUD; n = 18 without SUD). Relative to the non-SUD group, the SUD group exhibited significantly lower functional connectivity between the nucleus accumbens and a network of frontal cortical regions involved in cognitive control (dorsal anterior cingulate cortex, dorsolateral prefrontal cortex, and frontal operculum). There were no group differences in functional connectivity for the dorsal caudate or dorsal putamen. Moreover, the SUD group exhibited impairments in laboratory measures of cognitive-behavioral control, and individual differences in functional connectivity between nucleus accumbens and the frontal cortical regions were related to individual differences in measures of cognitive-behavioral control across groups. The strength of the relationship between functional connectivity and cognitive control did not differ between groups. These results indicate that SUD is associated with abnormal interactions between subcortical areas that process reward (nucleus accumbens) and cortical areas that govern cognitive-behavioral control. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.

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Available from: Arielle Baskin-Sommers, Sep 22, 2014
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    • "Not surprisingly, on inhibitory control tasks, nonaddicted individuals significantly outperform those who chronically use alcohol (Kamarajan et al., 2005), stimulants (Hester and Garavan, 2004;Monterosso et al., 2005), and opioids (Fu et al., 2008). Functional neuroimaging studies of addicted populations have demonstrated that the key regions associated with these control deficits are the anterior cingulate cortex , dorsolateral prefrontal cortex, and orbitofrontal cortex (Goldstein and Volkow, 2011;Motzkin et al., 2014), and structural neuroimaging studies have found that these regions are smaller in individuals with SUDs, with reductions proportionate to severity and/or length of use (Ersche et al., 2013;Goldstein and Volkow, 2011;Liu et al., 2009). Further , resting state functional connectivity strength within the executive control network is negatively correlated with AUD severity, which mediates the relationship between length of regular drinking and severity of alcohol problems (Weiland et al., 2014). "
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