title: Classifying adolescent attention-deficit/hyperactivity disorder (ADHD) based on functional and structural imaging.
abstract: Attention-deficit/hyperactivity disorder (ADHD) is a common disabling psychiatric disorder associated with consistent deficits in error processing, inhibition and regionally decreased grey matter volumes. The diagnosis is based on clinical presentation, interviews and questionnaires, which are to some degree subjective and would benefit from verification through biomarkers. Here, pattern recognition of multiple discriminative functional and structural brain patterns was applied to classify adolescents with ADHD and controls. Functional activation features in a Flanker/NoGo task probing error processing and inhibition along with structural magnetic resonance imaging data served to predict group membership using support vector machines (SVMs). The SVM pattern recognition algorithm correctly classified 77.78% of the subjects with a sensitivity and specificity of 77.78% based on error processing. Predictive regions for controls were mainly detected in core areas for error processing and attention such as the medial and dorsolateral frontal areas reflecting deficient processing in ADHD (Hart et al., in Hum Brain Mapp 35:3083-3094, 2014), and overlapped with decreased activations in patients in conventional group comparisons. Regions more predictive for ADHD patients were identified in the posterior cingulate, temporal and occipital cortex. Interestingly despite pronounced univariate group differences in inhibition-related activation and grey matter volumes the corresponding classifiers failed or only yielded a poor discrimination. The present study corroborates the potential of task-related brain activation for classification shown in previous studies. It remains to be clarified whether error processing, which performed best here, also contributes to the discrimination of useful dimensions and subtypes, different psychiatric disorders, and prediction of treatment success across studies and sites.
authors.affiliation: University Clinic for Child and Adolescent Psychiatry (UCCAP), University of Zurich, Neumünsterallee 9, 8032, Zurich, Switzerland.|PhD Program in Integrative Molecular Medicine, University of Zurich, Zurich, Switzerland.
authors.forename: Reto
authors.initials: R
authors.lastname: Iannaccone
authors.affiliation: University Clinic for Child and Adolescent Psychiatry (UCCAP), University of Zurich, Neumünsterallee 9, 8032, Zurich, Switzerland.|Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland.|Wellcome Trust Centre for Neuroimaging, University College London, London, UK.
authors.forename: Tobias U
authors.initials: TU
authors.lastname: Hauser
authors.affiliation: University Clinic for Child and Adolescent Psychiatry (UCCAP), University of Zurich, Neumünsterallee 9, 8032, Zurich, Switzerland.
authors.forename: Juliane
authors.initials: J
authors.lastname: Ball
authors.affiliation: University Clinic for Child and Adolescent Psychiatry (UCCAP), University of Zurich, Neumünsterallee 9, 8032, Zurich, Switzerland.|Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland.|Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.|Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, J5, 68159, Mannheim, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Brandeis
authors.affiliation: University Clinic for Child and Adolescent Psychiatry (UCCAP), University of Zurich, Neumünsterallee 9, 8032, Zurich, Switzerland.|Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland.|Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
authors.forename: Susanne
authors.initials: S
authors.lastname: Walitza
authors.affiliation: University Clinic for Child and Adolescent Psychiatry (UCCAP), University of Zurich, Neumünsterallee 9, 8032, Zurich, Switzerland. sbrem@kjpd.uzh.ch.|Neuroscience Center Zurich, University of Zurich and ETH Zurich, Zurich, Switzerland. sbrem@kjpd.uzh.ch.
authors.forename: Silvia
authors.initials: S
authors.lastname: Brem
mesh_terms: D000293:Adolescent; D001288:Attention / Q000502:physiology; D001289:Attention Deficit Disorder with Hyperactivity / Q000145:classification* / Q000175:diagnosis* / Q000523:psychology; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male
keywords: ADHD; Adolescence; Attention; Classification; fMRI