title: Hyperactivity in motor response inhibition networks in unmedicated children with attention deficit-hyperactivity disorder.
abstract: Hypo/reduced activity in motor response inhibition (RI) cerebral networks was recently proposed as a promising specific neurobiological marker of attention deficit-hyperactivity disorder (ADHD). Before adopting such a pattern as a key diagnosis tool, we aim to replicate in an independent study the mechanisms underlying reduced RI-related activity in ADHD, after controlling for potentially confounding effects.
  
  
  
  In this fMRI study, we investigated the neural networks mediating successful and failed motor RI in children with ADHD and typically developing children (TDC) using the stop-signal task (SST) paradigm.
  
  
  
  In contrast to hypofrontality predictions, children with ADHD exhibit increased neural activity during successful response inhibition in an RI-related brain network encompassing the indirect and/or hyperdirect pathways between the basal ganglia and cortex. Voxel-based morphometry analyses have further evidenced reduced grey matter volume in the left caudate in children with ADHD, which paralleled higher functional responses. Finally, connectivity analyses disclosed tighter coupling between a set of cortical regions and the right caudate as well as the right IFG, networks involved in successful RI.
  
  
  
  Hypo/reduced activity in RI cerebral networks in children with ADHD cannot at this time be considered as a systematic biomarker for ADHD.
authors.affiliation: a National Fund of Scientific Research (FNRS) Belgium.|b Laboratory of Experimental Neurology, Université Libre de Bruxelles (ULB) , Brussels , Belgium.|c Department of Neurology , Erasme Hospital, ULB , Brussels , Belgium.|d UR2NF-Neuropsychology and Functional Neuroimaging Research Unit at CRCN-Research Centre in Cognitive Neurosciences, ULB , Brussels , Belgium.|i UNI-ULB Neuroscience Institute, ULB , Brussels , Belgium.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Massat
authors.affiliation: d UR2NF-Neuropsychology and Functional Neuroimaging Research Unit at CRCN-Research Centre in Cognitive Neurosciences, ULB , Brussels , Belgium.|e Department of Clinical and Cognitive Neuropsychology, Erasme Hospital , ULB , Brussels , Belgium.|i UNI-ULB Neuroscience Institute, ULB , Brussels , Belgium.
authors.forename: Hichem
authors.initials: H
authors.lastname: Slama
authors.affiliation: d UR2NF-Neuropsychology and Functional Neuroimaging Research Unit at CRCN-Research Centre in Cognitive Neurosciences, ULB , Brussels , Belgium.|f INSERM , U894 , Paris , France.|i UNI-ULB Neuroscience Institute, ULB , Brussels , Belgium.
authors.forename: Thomas
authors.initials: T
authors.lastname: Villemonteix
authors.affiliation: d UR2NF-Neuropsychology and Functional Neuroimaging Research Unit at CRCN-Research Centre in Cognitive Neurosciences, ULB , Brussels , Belgium.|i UNI-ULB Neuroscience Institute, ULB , Brussels , Belgium.
authors.forename: Alison
authors.initials: A
authors.lastname: Mary
authors.affiliation: d UR2NF-Neuropsychology and Functional Neuroimaging Research Unit at CRCN-Research Centre in Cognitive Neurosciences, ULB , Brussels , Belgium.|g Hôpital Universitaire des Enfants Reine Fabiola (HUDERF), ULB , Brussels , Belgium.|i UNI-ULB Neuroscience Institute, ULB , Brussels , Belgium.
authors.forename: Simon
authors.initials: S
authors.lastname: Baijot
authors.affiliation: d UR2NF-Neuropsychology and Functional Neuroimaging Research Unit at CRCN-Research Centre in Cognitive Neurosciences, ULB , Brussels , Belgium.|i UNI-ULB Neuroscience Institute, ULB , Brussels , Belgium.
authors.forename: Ariadna
authors.initials: A
authors.lastname: Albajara Sáenz
authors.affiliation: h Department of Radiology , Clinics of Magnetic Resonance, Erasme Hospital ULB , Brussels , Belgium.
authors.forename: Danièle
authors.initials: D
authors.lastname: Balériaux
authors.affiliation: h Department of Radiology , Clinics of Magnetic Resonance, Erasme Hospital ULB , Brussels , Belgium.
authors.forename: Thierry
authors.initials: T
authors.lastname: Metens
authors.affiliation: h Department of Radiology , Clinics of Magnetic Resonance, Erasme Hospital ULB , Brussels , Belgium.
authors.forename: Martin
authors.initials: M
authors.lastname: Kavec
authors.affiliation: d UR2NF-Neuropsychology and Functional Neuroimaging Research Unit at CRCN-Research Centre in Cognitive Neurosciences, ULB , Brussels , Belgium.|i UNI-ULB Neuroscience Institute, ULB , Brussels , Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Peigneux
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000000981:diagnostic imaging / Q000503:physiopathology*; D001479:Basal Ganglia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002421:Caudate Nucleus / Q000000981:diagnostic imaging; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002648:Child; D063132:Connectome / Q000379:methods*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011597:Psychomotor Performance / Q000502:physiology*
keywords: ADHD; functional magnetic resonance imaging; response inhibition; striatum; voxel-based morphometry