title: Lower white matter microstructure in the superior longitudinal fasciculus is associated with increased response time variability in adults with attention-deficit/ hyperactivity disorder.
abstract: BACKGROUND
  Response time variability (RTV) is consistently increased in patients with attention-deficit/hyperactivity disorder (ADHD). A right-hemispheric frontoparietal attention network model has been implicated in these patients. The 3 main connecting fibre tracts in this network, the superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF) and the cingulum bundle (CB), show microstructural abnormalities in patients with ADHD. We hypothesized that the microstructural integrity of the 3 white matter tracts of this network are associated with ADHD and RTV.
  
  
  METHODS
  We examined RTV in adults with ADHD by modelling the reaction time distribution as an exponentially modified Gaussian (ex-Gaussian) function with the parameters μ, σ and τ, the latter of which has been attributed to lapses of attention. We assessed adults with ADHD and healthy controls using a sustained attention task. Diffusion tensor imaging-derived fractional anisotropy (FA) values were determined to quantify bilateral microstructural integrity of the tracts of interest.
  
  
  RESULTS
  We included 100 adults with ADHD and 96 controls in our study. Increased τ was associated with ADHD diagnosis and was linked to symptoms of inattention. An inverse correlation of τ with mean FA was seen in the right SLF of patients with ADHD, but no direct association between the mean FA of the 6 regions of interest with ADHD could be observed.
  
  
  CONCLUSIONS
  Regions of interest were defined a priori based on the attentional network model for ADHD and thus we might have missed effects in other networks.
  
  
  CONCLUSIONS
  This study suggests that reduced microstructural integrity of the right SLF is associated with elevated τ in patients with ADHD.
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Thomas
authors.initials: T
authors.lastname: Wolfers
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: A Marten H
authors.initials: AM
authors.lastname: Onnink
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Marcel P
authors.initials: MP
authors.lastname: Zwiers
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Arias-Vasquez
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Martine
authors.initials: M
authors.lastname: Hoogman
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Jeanette C
authors.initials: JC
authors.lastname: Mostert
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Cornelis C
authors.initials: CC
authors.lastname: Kan
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Dorine
authors.initials: D
authors.lastname: Slaats-Willemse
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Jan K
authors.initials: JK
authors.lastname: Buitelaar
authors.affiliation: From the Department of Human Genetics, Radboud University Medical Center (Wolfers, Arias-Vasquez, Mostert, Franke); the Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center ( Onnink, Arias-Vasquez, Hoogman, Kan, Franke); the Donders Centre for Cognitive Neuroimaging, Donders Institute for Brain, Cognition and Behaviour, Radboud University (Wolfers, Zwiers, Mostert); the Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center (Arias-Vasquez, Buitelaar); and the Karakter Child and Adolescent Psychiatry University Centre (Slaats-Willemse, Buitelaar), Nijmegen, the Netherlands.
authors.forename: Barbara
authors.initials: B
authors.lastname: Franke
mesh_terms: D000328:Adult; D016880:Anisotropy; D001288:Attention; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000503:physiopathology*; D038524:Diffusion Magnetic Resonance Imaging; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009412:Nerve Fibers; D009415:Nerve Net / Q000503:physiopathology*; D009483:Neuropsychological Tests; D011930:Reaction Time; D066127:White Matter / Q000503:physiopathology*