title: Age and gender effects in EEG coherence: II. Boys with attention deficit/hyperactivity disorder.
abstract: OBJECTIVE
  This study investigated intra-hemispheric and inter-hemispheric EEG coherences as a function of age in boys with different subtypes of Attention Deficit/Hyperactivity Disorder (AD/HD), in comparison with a control group of normal boys.
  
  
  METHODS
  Three groups of 40 children (AD/HD combined type, AD/HD inattentive type, and normal controls) participated. Each group contained 8 males in each 1 year band from 8 to 12 years. EEG was recorded from 21 sites during an eyes-closed resting condition. Wave-shape coherence was calculated for 8 intra-hemispheric electrode pairs (4 in each hemisphere), and 8 inter-hemispheric electrode pairs, within each of the delta, theta, alpha and beta bands.
  
  
  RESULTS
  Developmental effects in intra-hemispheric coherences at shorter and longer inter-electrode distances generally supported Thatcher's two-compartment model. Control boys showed evidence of development in longer-range inter-hemispheric coherences which was not apparent in AD/HD boys. Boys with AD/HD of the combined type showed qualitatively different anomalies than boys with AD/HD of the inattentive type.
  
  
  CONCLUSIONS
  EEG coherences in normal boys of this age range develop systematically with age in a non-linear fashion. Boys with AD/HD do not show this development. They display coherence anomalies which differ in nature between DSM-IV subtypes, suggesting differences which are not relatable to simple symptom severity.
  
  
  CONCLUSIONS
  The data reported here indicate differences in the development of EEG coherences in boys with AD/HD, and point to differences between the AD/HD subtypes which may help understanding of the disorder.
authors.affiliation: Brain & Behaviour Research Institute and Department of Psychology, University of Wollongong, Northfields Avenue, Wollongong NSW 2522, Australia. robert_barry@uow.edu.au
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Barry
authors.forename: Adam R
authors.initials: AR
authors.lastname: Clarke
authors.forename: Rory
authors.initials: R
authors.lastname: McCarthy
authors.forename: Mark
authors.initials: M
authors.lastname: Selikowitz
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Johnstone
authors.forename: Ching-I
authors.initials: CI
authors.lastname: Hsu
authors.forename: Dominique
authors.initials: D
authors.lastname: Bond
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Wallace
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Magee
mesh_terms: D000367:Age Factors; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D002648:Child; D004569:Electroencephalography / Q000379:methods*; D006801:Humans; D008297:Male; D012727:Sex Characteristics