title: Pitting temporal against spatial integration in schizophrenic patients.
abstract: Schizophrenic patients show strong impairments in visual backward masking possibly caused by deficits on the early stages of visual processing. The underlying aberrant mechanisms are not clearly understood. Spatial as well as temporal processing deficits have been proposed. Here, by combining a spatial with a temporal integration paradigm, we show further evidence that temporal but not spatial processing is impaired in schizophrenic patients. Eleven schizophrenic patients and ten healthy controls were presented with sequences composed of Vernier stimuli. Patients needed significantly longer presentation times for sequentially presented Vernier stimuli to reach a performance level comparable to that of healthy controls (temporal integration deficit). When we added spatial contextual elements to some of the Vernier stimuli, performance changed in a complex but comparable manner in patients and controls (intact spatial integration). Hence, temporal but not spatial processing seems to be deficient in schizophrenia.
authors.affiliation: Laboratory of Psychophysics, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland. michael.herzog@epfl.ch
authors.forename: Michael H
authors.initials: MH
authors.lastname: Herzog
authors.forename: Andreas
authors.initials: A
authors.lastname: Brand
mesh_terms: D000328:Adult; D001288:Attention; D003072:Cognition Disorders / Q000175:diagnosis* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual; D010470:Perceptual Masking; D010641:Phenotype; D010775:Photic Stimulation; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D013028:Space Perception; D013998:Time Perception; D014792:Visual Acuity