title: Gating of a novel brain potential is associated with perceptual anomalies in bipolar disorder.
abstract: OBJECTIVE
  Our laboratory recently identified the P85 gating ratio as a candidate biomarker for bipolar disorder. In order to evaluate the phenomenological significance of P85 gating, the current study examined reports of perceptual anomalies and their relationship to the P50 and P85 physiological measures of sensory gating.
  
  
  METHODS
  Reports of perceptual anomalies on the Structured Clinical Interview to Assess Perceptual Anomalies were compared in patients meeting DSM-IV criteria for paranoid schizophrenia (n = 66), schizoaffective disorder (n = 45), or bipolar I disorder (n = 42), and controls (n = 56), as well as their relationship with P85 and P50 gating.
  
  
  RESULTS
  The bipolar disorder group reported significantly more auditory, visual, and total anomalies than both the schizophrenia and control groups. The schizophrenia group also had more anomalies than the control group. Comparison of psychiatric subgroups revealed that the bipolar depressed, bipolar disorder with psychosis, and schizoaffective bipolar type groups reported the most anomalies compared to the other patient groups (bipolar disorder without psychosis, schizoaffective, bipolar manic). The total perceptual anomalies score and the P85 ratio significantly differentiated the bipolar disorder, schizoaffective, and paranoid schizophrenia groups from each other.
  
  
  CONCLUSIONS
  These findings provide evidence of the phenomenological significance of P85. The results also yield further support not only for the P85 ratio, but also for increased reports of perceptual anomalies as possible markers for bipolar disorder.
authors.affiliation: Department of Psychiatry and Human Behavior, University of California at Irvine, Irvine, CA, USA. jvpatter@uci.edu
authors.forename: Julie V
authors.initials: JV
authors.lastname: Patterson
authors.forename: Curt A
authors.initials: CA
authors.lastname: Sandman
authors.forename: Yi
authors.initials: Y
authors.lastname: Jin
authors.forename: Aaron S
authors.initials: AS
authors.lastname: Kemp
authors.forename: Steven G
authors.initials: SG
authors.lastname: Potkin
authors.forename: William E
authors.initials: WE
authors.lastname: Bunney
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001714:Bipolar Disorder / Q000150:complications* / Q000473:pathology*; D001921:Brain / Q000503:physiopathology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010468:Perceptual Disorders / Q000209:etiology*; D010812:Physical Stimulation; D011237:Predictive Value of Tests; D011618:Psychotic Disorders / Q000150:complications; D012559:Schizophrenia / Q000150:complications; D055139:Sensory Gating / Q000502:physiology*; D013223:Statistics as Topic