The time course of information-processing deficits in schizophrenia.

A visual backward masking task was used to specify the time course of the information-processing dysfunction in 19 schizophrenic patients and 15 matched control patients using novel interstimulus intervals. The authors found that the information-processing deficit in schizophrenic subjects occurred at interstimulus intervals of greater than 60 msec and less than 500 msec. These data are compared with the results of evoked-potential and other psychophysiological studies. The visual-processing impairment is specific and time-linked rather than a reflection of the effects of gross psychopathology or medication in schizophrenic individuals.