title: Event-related potentials in adolescents with schizophrenia and their siblings: a comparison with attention-deficit/hyperactivity disorder.
abstract: BACKGROUND
  Identifying trait markers specific to schizophrenia might uncover mechanisms underlying illness susceptibility. Previous research shows the N2 and P3 event-related potentials are abnormal in schizophrenia; specificity of these potential trait markers has not been well established.
  
  
  METHODS
  Electroencephalogram data were recorded from four adolescent groups: early-onset schizophrenia patients (SZ; n = 30); non-psychotic siblings of schizophrenia patients (SZ-SIB; n = 36); healthy control subjects (HC; n = 36); a neurodevelopmental attention-deficit/hyperactivity disorder (ADHD) comparison group (n = 27), during auditory oddball and visual go/no-go tasks. The P3 was measured to targets in the oddball task. The N2 and P3 were measured to go and no-go stimuli in the go/no-go task.
  
  
  RESULTS
  Compared with the HC group, the SZ and SZ-SIB groups showed significantly reduced auditory oddball P3 amplitude. Visual P3 amplitude was significantly reduced in the SZ group for no-go stimuli and the SZ-SIB group for go and no-go stimuli. The P3 amplitude in the ADHD group was not significantly reduced for either paradigm. The SZ and ADHD groups showed significantly reduced N2 amplitude in the go/no-go task; the SZ-SIB group was not significantly different from the HC group.
  
  
  CONCLUSIONS
  Results revealed reduced P3 amplitude in schizophrenia patients and adolescent non-psychotic siblings in an auditory oddball and a visual go/no-go task. The SZ-SIB and ADHD groups showed a different ERP profile when each was compared with the HC group: siblings showed reduced P3 amplitude in both tasks and normal N2 in the go/no-go task; the opposite pattern was observed in the ADHD group.
authors.affiliation: Developmental Psychiatry, University of Nottingham, Nottingham, England. maddie.groom@nottingham.ac.uk
authors.forename: Madeleine J
authors.initials: MJ
authors.lastname: Groom
authors.forename: Alan T
authors.initials: AT
authors.lastname: Bates
authors.forename: Georgina M
authors.initials: GM
authors.lastname: Jackson
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Calton
authors.forename: Peter F
authors.initials: PF
authors.lastname: Liddle
authors.forename: Chris
authors.initials: C
authors.lastname: Hollis
mesh_terms: D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000235:genetics / Q000502:physiology; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics* / Q000503:physiopathology; D001307:Auditory Perception / Q000502:physiology; D002540:Cerebral Cortex / Q000503:physiopathology; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000235:genetics; D005071:Evoked Potentials / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology; D010641:Phenotype; D011597:Psychomotor Performance / Q000502:physiology; D012559:Schizophrenia / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D012569:Schizotypal Personality Disorder / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D035781:Siblings