title: Neurologic examination abnormalities in children with bipolar disorder or attention-deficit/hyperactivity disorder.
abstract: BACKGROUND
  Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BPD) are frequently comorbid and overlapping diagnoses. To move beyond diagnosis toward unique pathophysiology, we evaluated both ADHD and BPD children for neurologic examination abnormalities (NEAs) in comparison with normal control (NC) children.
  
  
  METHODS
  We performed the Revised Physical and Neurological Examination for Soft Signs in three groups (ADHD, BPD, NC). Then, a rater blind to diagnosis evaluated their motor performance. Results were analyzed with a multiple analysis of covariance.
  
  
  RESULTS
  Subjects with ADHD were impaired on repetitive task reaction time. In contrast, pediatric BPD subjects, both with and without comorbid ADHD, were impaired on sequential task reaction time.
  
  
  CONCLUSIONS
  This differential pattern of NEAs by diagnosis suggests pathophysiologic differences between ADHD and BPD in children. Repetitive motor performance requires inhibition of nonrelevant movements; ADHD subjects' impairment in this domain supports the hypothesis that ADHD involves a core deficit of fronto-striato-basal ganglia neurocircuitry. In contrast, BPD subjects' impaired sequential motor performance is consistent with behavioral data showing impaired attentional set-shifting and reversal learning in BPD subjects. Further study, going beyond symptom description to determine pathophysiologic differences, is required to refine neuronal models of these often comorbid diagnoses.
authors.affiliation: National Institute of Mental Health, Pediatrics and Developmental Neuropsychiatry Branch, 10 Center Drive MSC 1255, Building 10/Room 4N208, Bethesda MD 20892-1255, USA. Dicksted@intra.nimh.nih.gov
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Dickstein
authors.forename: Marjorie
authors.initials: M
authors.lastname: Garvey
authors.forename: Anne G
authors.initials: AG
authors.lastname: Pradella
authors.forename: Deanna K
authors.initials: DK
authors.lastname: Greenstein
authors.forename: Wendy S
authors.initials: WS
authors.lastname: Sharp
authors.forename: F Xavier
authors.initials: FX
authors.lastname: Castellanos
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Pine
authors.forename: Ellen
authors.initials: E
authors.lastname: Leibenluft
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications / Q000503:physiopathology* / Q000523:psychology; D001714:Bipolar Disorder / Q000150:complications / Q000503:physiopathology* / Q000523:psychology; D002648:Child; D003071:Cognition / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D009460:Neurologic Examination; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology; D012193:Reversal Learning / Q000502:physiology