title: Whole-brain structural topology in adult attention-deficit/hyperactivity disorder: Preserved global - disturbed local network organization.
abstract: Prior studies demonstrate altered organization of functional brain networks in attention-deficit/hyperactivity disorder (ADHD). However, the structural underpinnings of these functional disturbances are poorly understood. In the current study, we applied a graph-theoretic approach to whole-brain diffusion magnetic resonance imaging data to investigate the organization of structural brain networks in adults with ADHD and unaffected controls using deterministic fiber tractography. Groups did not differ in terms of global network metrics - small-worldness, global efficiency and clustering coefficient. However, there were widespread ADHD-related effects at the nodal level in relation to local efficiency and clustering. The affected nodes included superior occipital, supramarginal, superior temporal, inferior parietal, angular and inferior frontal gyri, as well as putamen, thalamus and posterior cerebellum. Lower local efficiency of left superior temporal and supramarginal gyri was associated with higher ADHD symptom scores. Also greater local clustering of right putamen and lower local clustering of left supramarginal gyrus correlated with ADHD symptom severity. Overall, the findings indicate preserved global but altered local network organization in adult ADHD implicating regions underpinning putative ADHD-related neuropsychological deficits.
authors.affiliation: Department of Experimental-Clinical and Health Psychology, Ghent University, Henri Dunantlaan 2, Ghent B-9000, Belgium.
authors.forename: Justina
authors.initials: J
authors.lastname: Sidlauskaite
authors.affiliation: School of Psychology, Faculty of Health Sciences, Australian Catholic University, 115 Victoria Parade, Melbourne, VIC 3065, Australia.
authors.forename: Karen
authors.initials: K
authors.lastname: Caeyenberghs
authors.affiliation: Department of Experimental-Clinical and Health Psychology, Ghent University, Henri Dunantlaan 2, Ghent B-9000, Belgium ; Developmental Brain-Behaviour Unit, Psychology, University of Southampton, Shackleton Building (B44), Highfield Campus, Southampton SO17 1BJ, United Kingdom.
authors.forename: Edmund
authors.initials: E
authors.lastname: Sonuga-Barke
authors.affiliation: Department of Experimental-Clinical and Health Psychology, Ghent University, Henri Dunantlaan 2, Ghent B-9000, Belgium.
authors.forename: Herbert
authors.initials: H
authors.lastname: Roeyers
authors.affiliation: Department of Experimental-Clinical and Health Psychology, Ghent University, Henri Dunantlaan 2, Ghent B-9000, Belgium.
authors.forename: Jan R
authors.initials: JR
authors.lastname: Wiersema
mesh_terms: D000328:Adult; D001289:Attention Deficit Disorder with Hyperactivity / Q000473:pathology*; D001921:Brain / Q000473:pathology*; D016000:Cluster Analysis; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D009434:Neural Pathways / Q000473:pathology; D055815:Young Adult
keywords: Attention deficit/hyperactivity disorder; Deterministic tractography; Diffusion MRI; Graph theory