title: Network Structure among Brain Systems in Adult ADHD is Uniquely Modified by Stimulant Administration.
abstract: Current research in connectomics highlights that self-organized functional networks or "communities" of cortical areas can be detected in the adult brain. This perspective may provide clues to mechanisms of treatment response in psychiatric conditions. Here we examine functional brain community topology based on resting-state fMRI in adult Attention-Deficit/Hyperactivity Disorder (ADHD; n = 22) and controls (n = 31). We sought to evaluate ADHD patterns in adulthood and their modification by short term stimulants administration. Participants with ADHD were scanned one or two weeks apart, once with medication and once without; comparison participants were scanned at one time-point. Functional connectivity was estimated from these scans and community detection applied to determine cortical network topology. Measures of change in connectivity profile were calculated via a graph measure, termed the Node Dissociation Index (NDI). Compared to controls, several cortical networks had atypical connectivity in adults with ADHD when withholding stimulants, as measured by NDI. In most networks stimulants significantly reduced, but did not eliminate, differences in the distribution of connections between key brain systems relative to the control sample. These findings provide an enriched model of connectivity in ADHD and demonstrate how stimulants may exert functional effects by altering connectivity profiles in the brain.
authors.affiliation: Department of Behavioral Neuroscience, Oregon Health & Science University, USA.|Department of Psychiatry, Oregon Health & Science University, USA.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Cary
authors.affiliation: Department of Behavioral Neuroscience, Oregon Health & Science University, USA.
authors.forename: Siddharth
authors.initials: S
authors.lastname: Ray
authors.affiliation: Department of Behavioral Neuroscience, Oregon Health & Science University, USA.
authors.forename: David S
authors.initials: DS
authors.lastname: Grayson
authors.affiliation: Department of Behavioral Neuroscience, Oregon Health & Science University, USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Painter
authors.affiliation: Department of Behavioral Neuroscience, Oregon Health & Science University, USA.
authors.forename: Samuel
authors.initials: S
authors.lastname: Carpenter
authors.affiliation: Department of Psychiatry, Oregon Health & Science University, USA.
authors.forename: Leeza
authors.initials: L
authors.lastname: Maron
authors.affiliation: Department of Psychological and Brain Sciences, Indiana University, USA.
authors.forename: Olaf
authors.initials: O
authors.lastname: Sporns
authors.affiliation: Department of Psychiatry, Oregon Health & Science University, USA.
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Stevens
authors.affiliation: Department of Psychiatry, Oregon Health & Science University, USA.
authors.forename: Joel T
authors.initials: JT
authors.lastname: Nigg
authors.affiliation: Department of Behavioral Neuroscience, Oregon Health & Science University, USA.|Department of Psychiatry, Oregon Health & Science University, USA.|Advanced Imaging Research Center, Oregon Health & Science University, USA.
authors.forename: Damien A
authors.initials: DA
authors.lastname: Fair
mesh_terms: D000293:Adolescent; D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology*; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000503:physiopathology*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use*; D015331:Cohort Studies; D063132:Connectome; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology; D011569:Psychiatric Status Rating Scales; D012146:Rest; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000697:Central Nervous System Stimulants
keywords: ADHD; MRI; functional connectivity; resting state; stimulants