title: Attention-deficit/hyperactivity disorder: cognitive evoked potential (P300) topography predicts treatment response to methylphenidate.
abstract: OBJECTIVE
  Auditory cognitive evoked potential (P300) topography predicts robust response to the stimulant pemoline in patients with attention-deficit/hyperactivity disorder (ADHD). Patients with a right fronto-central to parietal (FC2:P4) auditory P300 amplitude ratio >0.5 respond robustly to pemoline, whereas others do not. This study was performed to demonstrate whether the same test and ratio predict treatment response to methylphenidate.
  
  
  METHODS
  Patients aged 6-12 with DSM-IV diagnosis of ADHD were administered auditory and visual cognitive evoked potential (P300) testing. They then underwent single-blind treatment with an extended-release version of methylphenidate. Robust response was defined as a 60% decrease from baseline in a parent rated ADHD rating scale.
  
  
  RESULTS
  Nine of 20 subjects responded robustly. They did not differ from the non-robust responders in age, baseline attention or hyperactivity ratings, or any P300 parameter except auditory P300 topography. A FC2:P4 auditory P300 amplitude ratio >0.5 predicted robust response with a positive predictive value of 0.67 and a negative predictive value of 0.73.
  
  
  CONCLUSIONS
  The ratio of right fronto-central to parietal auditory P300 amplitude predicts response to stimulants in patients with ADHD. As non-stimulant treatments are approved for the treatment of ADHD, tests such as this may help pinpoint whether to use a stimulant or a medicine with some other mechanism of action.
authors.affiliation: Attention Disorders Institute, 44199 Dequindre, Ste. 311, Troy, MI 48085, USA. sangalrb@sbcglobal.net
authors.forename: R Bart
authors.initials: RB
authors.lastname: Sangal
authors.forename: JoAnne M
authors.initials: JM
authors.lastname: Sangal
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy* / Q000503:physiopathology* / Q000523:psychology; D000697:Central Nervous System Stimulants / Q000627:therapeutic use*; D002648:Child; D003071:Cognition / Q000502:physiology*; D004311:Double-Blind Method; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008297:Male; D008774:Methylphenidate / Q000627:therapeutic use*; D010296:Parietal Lobe / Q000503:physiopathology; D010389:Pemoline / Q000627:therapeutic use; D011237:Predictive Value of Tests; D013702:Temporal Lobe / Q000503:physiopathology
chemical_list: D000697:Central Nervous System Stimulants; D008774:Methylphenidate; D010389:Pemoline