title: Altered frontal pole development affects self-generated spatial working memory in ADHD.
abstract: BACKGROUND
  Spatial working memory (SWM) dysfunction is a feature of attention deficit hyperactivity disorder (ADHD). Previous studies suggested that behavioral performance in self-generated SWM improves through development in children with and without ADHD. Nevertheless, developmental changes in the neural underpinnings of self-generated SWM are unknown.
  
  
  METHODS
  Using near-infrared spectroscopy, hemodynamic activity in the prefrontal cortex (PFC) was measured in 30 children with ADHD (9.5 ± 1.6 years-old) and 35 TD children (9.0 ± 1.6 years-old) while they performed a self-generated SWM task. We then investigated correlations between age and behavioral performance, and between age and hemodynamic activity in the PFC for each group.
  
  
  RESULTS
  Both groups showed a negative correlation with age and number of errors [ADHD: r(28)=-0.37, p=0.040; TD: r(33)=-0.59, p<0.001], indicating that self-generated SWM improves through development. The TD group showed a positive correlation between age and oxygenated hemoglobin in the frontal pole [10ch: r(33)=0.41, p=0.013; 11ch; r(33)=0.44, p=0.008] and bilateral lateral PFC [4ch: r(33)=0.34, p=0.049; 13ch; r(33)=0.54, p=0.001], while no significant correlation was found in the ADHD group. Furthermore, regression slopes for the frontal pole significantly differed between the TD and ADHD groups [10ch: t(61)=2.35, p=0.021; 11ch: t(61)=2.05, p=0.044].
  
  
  CONCLUSIONS
  Children with ADHD showed abnormalities in functional maturation of the frontal pole, which plays a role in manipulating and maintaining information associated with self-generated behavior.
authors.affiliation: Developmental Emotional Intelligence, Division of Developmental Higher Brain Functions, Department of Child Development United Graduate School of Child Development, University of Fukui, Japan.
authors.forename: Sumiyoshi
authors.initials: S
authors.lastname: Arai
authors.affiliation: Developmental Emotional Intelligence, Division of Developmental Higher Brain Functions, Department of Child Development United Graduate School of Child Development, University of Fukui, Japan; Research Center for Child Mental Development, University of Fukui, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Okamoto
authors.affiliation: Department Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Japan; Department of Child and Adolescent Psychological Medicine, University of Fukui, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Fujioka
authors.affiliation: Department Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Japan; Department of Informatics, Graduate School of Informatics and Engineering, The University of Electro-Communications, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Inohara
authors.affiliation: Department Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Japan; Department of Child and Adolescent Mental Health, National Institute of Mental Health, National Center of Neurology and Psychiatry, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Ishitobi
authors.affiliation: Department Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Matsumura
authors.affiliation: Developmental Emotional Intelligence, Division of Developmental Higher Brain Functions, Department of Child Development United Graduate School of Child Development, University of Fukui, Japan; Research Center for Child Mental Development, University of Fukui, Japan.
authors.forename: Minyoung
authors.initials: M
authors.lastname: Jung
authors.affiliation: Hiratani Clinic for Developmental Disorders of Children, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Kawamura
authors.affiliation: Department of Child and Adolescent Psychological Medicine, University of Fukui, Japan; Advanced Biomedical Sciences Course, Graduate School of Medical Sciences, University of Fukui, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Takiguchi
authors.affiliation: Developmental Emotional Intelligence, Division of Developmental Higher Brain Functions, Department of Child Development United Graduate School of Child Development, University of Fukui, Japan; Research Center for Child Mental Development, University of Fukui, Japan; Department of Child and Adolescent Psychological Medicine, University of Fukui, Japan.
authors.forename: Akemi
authors.initials: A
authors.lastname: Tomoda
authors.affiliation: Department Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Wada
authors.affiliation: Hiratani Clinic for Developmental Disorders of Children, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Hiratani
authors.affiliation: Tokyo University of Social Welfare, Japan.
authors.forename: Naomi
authors.initials: N
authors.lastname: Matsuura
authors.affiliation: Developmental Emotional Intelligence, Division of Developmental Higher Brain Functions, Department of Child Development United Graduate School of Child Development, University of Fukui, Japan; Research Center for Child Mental Development, University of Fukui, Japan; Department Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Japan; Department of Child and Adolescent Psychological Medicine, University of Fukui, Japan. Electronic address: hirotaka@u-fukui.ac.jp.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Kosaka
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D009483:Neuropsychological Tests; D017397:Prefrontal Cortex / Q000378:metabolism; D065854:Spatial Navigation / Q000502:physiology*; D019265:Spectroscopy, Near-Infrared / Q000379:methods
keywords: Attention deficit hyperactivity disorder (ADHD); Cambridge Automated Neuropsychological Battery (CANTAB®); Development; Near-infrared spectroscopy (NIRS); Prefrontal cortex (PFC); Self-generated spatial working memory (SWM)