title: Distinct intrinsic functional brain network abnormalities in methamphetamine-dependent patients with and without a history of psychosis.
abstract: Chronic methamphetamine use is associated with executive functioning deficits that suggest dysfunctional cognitive control networks (CCNs) in the brain. Likewise, abnormal connectivity between intrinsic CCNs and default mode networks (DMNs) has also been associated with poor cognitive function in clinical populations. Accordingly, we tested the extent to which methamphetamine use predicts abnormal connectivity between these networks, and whether, as predicted, these abnormalities are compounded in patients with a history of methamphetamine-associated psychosis (MAP). Resting-state fMRI data were acquired from 46 methamphetamine-dependent patients [19 with MAP, 27 without (MD)], as well as 26 healthy controls (CTRL). Multivariate network modelling and whole-brain voxel-wise connectivity analyses were conducted to identify group differences in intrinsic connectivity across four cognitive control and three DMN networks identified using an independent components analysis approach (meta-ICA). The relationship of network connectivity and psychotic symptom severity, as well as antipsychotic treatment and methamphetamine use variables, was also investigated. Robust evidence of hyper-connectivity was observed between the right frontoparietal and anterior DMN networks in MAP patients, and 'normalized' with increased duration of treatment with antipsychotics. Attenuation of anticorrelated anterior DMN-dorsal attention network activity was also restricted to this group. Elevated coupling detected in MD participants between anterior and posterior DMN networks became less apparent with increasing duration of abstinence from methamphetamine. In summary, we observed both alterations of RSN connectivity between DMN networks with chronic methamphetamine exposure, as well as DMN-CCN coupling abnormalities consistent with possible MAP-specific frontoparietal deficits in the biasing of task-appropriate network activity.
authors.affiliation: Department of Psychiatry Mental Health, University of Cape Town, South Africa.
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Ipser
authors.affiliation: Department of Psychiatry Mental Health, University of Cape Town, South Africa.|Anxiety and Stress Disorders Research Unit, Medical Research Council, South Africa.
authors.forename: Anne
authors.initials: A
authors.lastname: Uhlmann
authors.affiliation: MRC/UCT Medical Imaging Research Unit, Department of Human Biology, University of Cape Town, South Africa.|African Institute for Mathematical Sciences, South Africa.|Scientific and Statistical Computing Core, National Institute of Mental Health, Bethesda, MD, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Taylor
authors.affiliation: Center of Excellence for Pharmaceutical Sciences, North-West University, South Africa.
authors.forename: Brian H
authors.initials: BH
authors.lastname: Harvey
authors.affiliation: Department of Psychiatry Mental Health, University of Cape Town, South Africa.
authors.forename: Don
authors.initials: D
authors.lastname: Wilson
authors.affiliation: Department of Psychiatry Mental Health, University of Cape Town, South Africa.|Anxiety and Stress Disorders Research Unit, Medical Research Council, South Africa.
authors.forename: Dan J
authors.initials: DJ
authors.lastname: Stein
mesh_terms: D000328:Adult; D019969:Amphetamine-Related Disorders / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000523:psychology; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001288:Attention; D001921:Brain / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D059907:Functional Neuroimaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008694:Methamphetamine; D009434:Neural Pathways; D011618:Psychotic Disorders / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology / Q000523:psychology; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D008694:Methamphetamine
keywords: Methamphetamine-associated psychosis; cognitive control networks; resting-state functional connectivity