The Effects of Clozapine and Risperidone on Spatial Working Memory in Schizophrenia

Abstract
The purpose of this investigation was to evaluate the effects of clozapine and risperidone on spatial working memory in patients with schizophrenia. Spatial working memory performance was evaluated at baseline and after 17 and 29 weeks in 97 patients with schizophrenia participating in a multisite trial. Compared with baseline performance while receiving conventional antipsychotic medication, risperidone improved, and clozapine worsened, spatial working memory performance. The differential effects of these medications on spatial working memory may be due to the anticholinergic effects of clozapine and prefrontal dopamine-enhancing effects of risperidone.