title: Neural correlates of visuospatial working memory in attention-deficit/hyperactivity disorder and healthy controls.
abstract: Impaired visuospatial working memory (VSWM) is suggested to be a core neurocognitive deficit in attention-deficit/hyperactivity disorder (ADHD), yet the underlying neural activation patterns are poorly understood. Furthermore, it is unclear to what extent age and gender effects may play a role in VSWM-related brain abnormalities in ADHD. Functional magnetic resonance imaging (fMRI) data were collected from 109 individuals with ADHD (60% male) and 103 controls (53% male), aged 8-25 years, during a spatial span working memory task. VSWM-related brain activation was found in a widespread network, which was more widespread compared with N-back tasks used in the previous literature. Higher brain activation was associated with higher age and male gender. In comparison with controls, individuals with ADHD showed greater activation in the left inferior frontal gyrus (IFG) and the lateral frontal pole during memory load increase, effects explained by reduced activation on the low memory load in the IFG pars triangularis and increased activation during high load in the IFG pars opercularis. Age and gender effects did not differ between controls and individuals with ADHD. Results indicate that individuals with ADHD have difficulty in efficiently and sufficiently recruiting left inferior frontal brain regions with increasing task difficulty.
authors.affiliation: Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands. Electronic address: h.van.ewijk@vu.nl.
authors.forename: Hanneke
authors.initials: H
authors.lastname: van Ewijk
authors.affiliation: Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Wouter D
authors.initials: WD
authors.lastname: Weeda
authors.affiliation: Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Dirk J
authors.initials: DJ
authors.lastname: Heslenfeld
authors.affiliation: Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Marjolein
authors.initials: M
authors.lastname: Luman
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands.
authors.forename: Catharina A
authors.initials: CA
authors.lastname: Hartman
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands.
authors.forename: Pieter J
authors.initials: PJ
authors.lastname: Hoekstra
authors.affiliation: Departments of Psychiatry and of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, NY, USA.
authors.forename: Stephen V
authors.initials: SV
authors.lastname: Faraone
authors.affiliation: Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Centre for Neuroscience, Departments of Human Genetics and Psychiatry, Nijmegen, The Netherlands.
authors.forename: Barbara
authors.initials: B
authors.lastname: Franke
authors.affiliation: Radboud University Medical Center, Donders Institute for Brain, Cognition and Behavior, Centre for Neuroscience, Department of Cognitive Neuroscience, Nijmegen, The Netherlands; Karakter, Child and Adolescent Psychiatry University Centre, Nijmegen, The Netherlands.
authors.forename: Jan K
authors.initials: JK
authors.lastname: Buitelaar
authors.affiliation: Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Jaap
authors.initials: J
authors.lastname: Oosterlaan
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology* / Q000523:psychology; D001921:Brain / Q000503:physiopathology*; D016022:Case-Control Studies; D002648:Child; D003118:Color Perception / Q000502:physiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012016:Reference Values; D012691:Serial Learning / Q000502:physiology*; D012737:Sex Factors; D065853:Spatial Learning / Q000502:physiology*; D055815:Young Adult
keywords: ADHD; Age; Children; Development; Gender; Spatial span; fMRI