ABSTRACT
OBJECTIVES: The aim of this study is to evaluate the effect of risperidone on attention and information-processing in schizophrenic patients after 8 weeks of treatment and to determine whether any improvement on cognitive function relates to improvement in psychopathology. METHODS: The subjects were 29 schizophrenic inpatients with active psychotic symptoms and the controls were 25 normal volunteers. Pre- and post-treatment clinical symptoms were assessed by Positive and Negative Syndrome Scale, Clinical Global Impression and Extrapyramidal Symptom Rating Scale. Vigilance, continuous atttention, the speed of information-processing and fine motor coordinations were assessed by standardized computerized neurocognitive function tests. RESULTS: At baseline, patients showed significantly poor vigilance and continuous attention than normal controls and these functions were not improved after treatment. The positive and negative symptoms and the general psychopathology were significantly improved. The only item of cognitive tasks signi-fica-ntly improved after treatment was decision time to complex audio-visual stimuli in information-processing task. This improvement was not related to the improvements in psychopathology. The level of extrapyramidal symptoms was not related with any of the cognitive fucntion tests items. CONCLUSIONS: Treatment with risperidone appeared to exert a favorable effect on the speed of information-processing and this appeared to be due to a direct pharmacodynamic characteristics of the drug.