Altered gray matter organization in children and adolescents with ADHD: a structural covariance connectome study.
Although multiple studies have reported structural deficits in multiple brain regions in attention-deficit hyperactivity disorder (ADHD), we do not yet know if these deficits reflect a more systematic disruption to the anatomical organization of large-scale brain networks. Here we used a graph theoretical approach to quantify anatomical organization in children and adolescents with ADHD. We generated anatomical networks based on covariance of gray matter volumes from 92 regions across the brain in children and adolescents with ADHD (n=34) and age- and sex-matched healthy controls (n=28). Using graph theory, we computed metrics that characterize both the global organization of anatomical networks (interconnectivity (clustering), integration (path length) and balance of global integration and localized segregation (small-worldness)) and their local nodal measures (participation (degree) and interaction (betweenness) within a network). Relative to Controls, ADHD participants exhibited altered global organization reflected in more clustering or network segregation. Locally, nodal degree and betweenness were increased in the subcortical amygdalae in ADHD, but reduced in cortical nodes in the anterior cingulate, posterior cingulate, mid temporal pole and rolandic operculum. In ADHD, anatomical networks were disrupted and reflected an emphasis on subcortical local connections centered around the amygdala, at the expense of cortical organization. Brains of children and adolescents with ADHD may be anatomically configured to respond impulsively to the automatic significance of stimulus input without having the neural organization to regulate and inhibit these responses. These findings provide a novel addition to our current understanding of the ADHD connectome.
Brain Dynamics Centre, The Westmead Institute for Medical Research, The University of Sydney, Westmead Sydney, NSW, Australia.
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Griffiths
Brain Dynamics Centre, The Westmead Institute for Medical Research, The University of Sydney, Westmead Sydney, NSW, Australia.|Sydney Translational Imaging Laboratory, Heart Research Institute, Charles Perkins Centre and Sydney Medical School, University of Sydney, Sydney, NSW, Australia.
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Grieve
Brain Dynamics Centre, The Westmead Institute for Medical Research, The University of Sydney, Westmead Sydney, NSW, Australia.|Adolescent and Young Adult Medicine, Westmead Hospital, Sydney, NSW, Australia.|Centre for Research into Adolescents' Health (CRASH), Sydney, NSW, Australia.
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Kohn
Brain Dynamics Centre, The Westmead Institute for Medical Research, The University of Sydney, Westmead Sydney, NSW, Australia.|Adolescent and Young Adult Medicine, Westmead Hospital, Sydney, NSW, Australia.|Centre for Research into Adolescents' Health (CRASH), Sydney, NSW, Australia.
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Clarke
Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA.|Department of Sierra-Pacific MIRECC, VA Palo Alto Health Care System, Palo Alto, CA, USA.
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Williams
Brain Dynamics Centre, The Westmead Institute for Medical Research, The University of Sydney, Westmead Sydney, NSW, Australia.|Discipline of Psychiatry, Sydney Medical School, Westmead, Sydney, NSW, Australia.
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Korgaonkar
D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000000981:diagnostic imaging* / Q000473:pathology*; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology*; D016022:Case-Control Studies; D002648:Child; D063132:Connectome; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000000981:diagnostic imaging* / Q000473:pathology*