title: Model-free functional connectivity and impulsivity correlates of alcohol dependence: a resting-state study.
abstract: Alcohol dependence is characterized by impulsiveness toward consumption despite negative consequences. Although neuro-imaging studies have implicated some regions underlying this disorder, there is little information regarding its large-scale connectivity pattern. This study investigated the within- and between-network functional connectivity (FC) in alcohol dependence and examined its relationship with clinical impulsivity measures. Using probabilistic independent component analysis on resting-state functional magnetic resonance imaging (rs-fMRI) data from 25 alcohol-dependent (AD) and 26 healthy control (HC) participants, we compared the within- and between-network FC between AD and HC. Then, the relationship between FC and impulsiveness as measured by the Barratt Impulsiveness Scale (BIS-11), the UPPS-P Impulsive Scale and the delay discounting task (DDT), was explored. Compared with HC, AD exhibited increased within-network FC in salience (SN), default mode (DMN), orbitofrontal cortex (OFCN), left executive control (LECN) and amygdala-striatum (ASN) networks. Increased between-network FC was found among LECN, ASN and SN. Between-network FC correlations were significantly negative between Negative-Urgency and OFCN pairs with right executive control network (RECN), anterior DMN (a-DMN) and posterior DMN (p-DMN) in AD. DDT was significantly correlated with the between-network FC among the LECN, a-DMN and SN in AD. These findings add evidence to the concept of altered within-network FC and also highlight the role of between-network FC in the pathophysiology of AD. Additionally, this study suggests differential neurobiological bases for different clinical measures of impulsivity that may be used as a systems-level biomarker for alcohol dependence severity and treatment efficacy.
authors.affiliation: Section on Brain Electrophysiology and Imaging, LCTS, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Xi
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Section on Brain Electrophysiology and Imaging, LCTS, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Cortes
authors.affiliation: Section on Brain Electrophysiology and Imaging, LCTS, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Karan
authors.initials: K
authors.lastname: Mathur
authors.affiliation: Laboratory of Neuroimaging, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Dardo
authors.initials: D
authors.lastname: Tomasi
authors.affiliation: Section on Brain Electrophysiology and Imaging, LCTS, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Reza
authors.initials: R
authors.lastname: Momenan
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000503:physiopathology*; D001921:Brain / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods*; D005260:Female; D006801:Humans; D007175:Impulsive Behavior / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012146:Rest; D055815:Young Adult
keywords: Alcohol dependence; ICA; fMRI; functional connectivity; impulsivity; resting state