title: Brain mapping of bilateral interactions in attention deficit hyperactivity disorder and control boys.
abstract: OBJECTIVE
  Children with attention deficit hyperactivity disorder (ADHD) are thought to have deficits in attentional control, whereas the status of deficits at visual and pre-motor processing stages is unclear.
  
  
  METHODS
  The timing of such deficits was examined with event-related potential (ERP) microstates (stimulus- and response-related) and continuous force recordings in 15 ADHD and 16 control boys in a choice reaction time task. Unilateral and bilateral stimulus and response conditions were used to assess bilateral interactions at visual, central, and pre-motor stages.
  
  
  RESULTS
  ADHD boys showed poorer performance, particularly in the bilateral conditions. In the visual P1 microstates, they exhibited less suppression of visual evoked potential (VEP) amplitudes but similar speeding of VEP latencies in the bilateral compared to the summed unilateral condition. The central P3 and pre-/post-response microstates were attenuated and topographically altered in ADHD boys. The attenuation was most pronounced in the bilateral condition and was similar for stimulus- and response-related averages. The lateralized readiness potential was also reduced in ADHD boys; this was most pronounced for the left hand responses.
  
  
  CONCLUSIONS
  Brain mapping during uni- and bilateral stimulus and response conditions thus indicates multilevel deficits in ADHD boys affecting visuo-attentional, central, and pre-motor processes.
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Zurich, Neumünsterallee 9, CH-8032, Zurich, Switzerland.
authors.forename: J
authors.initials: J
authors.lastname: Steger
authors.forename: K
authors.initials: K
authors.lastname: Imhof
authors.forename: H
authors.initials: H
authors.lastname: Steinhausen
authors.forename: D
authors.initials: D
authors.lastname: Brandeis
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D001931:Brain Mapping; D002648:Child; D003265:Contingent Negative Variation; D004569:Electroencephalography; D004585:Electrooculography; D005071:Evoked Potentials; D005385:Fingers; D007839:Functional Laterality; D006801:Humans; D007361:Intelligence Tests; D008297:Male; D010775:Photic Stimulation; D011312:Pressure; D011597:Psychomotor Performance; D011930:Reaction Time; D013933:Thumb