title: Information processing deficits of schizophrenia patients: relationship to clinical ratings, gender and medication status.
abstract: Information processing deficits were explored in a large cohort of schizophrenia patients (N = 125) and non-psychiatric subjects (N = 52). Gender, medication status and symptom factors were assessed relative to measures of performance in critical stimulus duration (CSD), visual backward masking (VBM) and auditory reaction time (RT) paradigms. Schizophrenia patients exhibited significant impairments in measures of CSD, VBM and both RT speed and RT set. Females in both groups had inflated CSDs relative to males. Female schizophrenia patients showed slower RTs and elevated RT set scores, but comparable VBM performance, when compared to males. This gender difference was not observed in the non-psychiatric subjects. To test the hypothesis that impaired performance in the VBM and RT paradigms would be related to negative symptoms and thought disorder, regression analyses were performed using factor scores derived from a factor analysis of SANS and SAPS items that generated three symptom factors: negative, disorganized, and reality distortion. Significant variance in performance on VBM and RT measures was accounted for only by the negative symptom factor. We conclude that VBM and RT assess information processing deficits in schizophrenia patients that are more related to the negative versus positive or disorganized symptoms of schizophrenia. It is possible that VBM and RT share overlapping or interacting neural substrates.
authors.affiliation: Department of Psychiatry, University of California, San Diego, La Jolla 92093-0804, USA.
authors.forename: K S
authors.initials: KS
authors.lastname: Cadenhead
authors.forename: M A
authors.initials: MA
authors.lastname: Geyer
authors.forename: R W
authors.initials: RW
authors.lastname: Butler
authors.forename: W
authors.initials: W
authors.lastname: Perry
authors.forename: J
authors.initials: J
authors.lastname: Sprock
authors.forename: D L
authors.initials: DL
authors.lastname: Braff
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003072:Cognition Disorders / Q000209:etiology* / Q000503:physiopathology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D010470:Perceptual Masking / Q000502:physiology; D011597:Psychomotor Performance; D011930:Reaction Time; D012559:Schizophrenia / Q000150:complications* / Q000188:drug therapy / Q000503:physiopathology; D012565:Schizophrenic Psychology; D012684:Sensory Thresholds / Q000502:physiology; D012737:Sex Factors; D014796:Visual Perception / Q000502:physiology*