Participants with schizophrenia displayed improvement in most cognitive tasks, but practice was more likely than cognitive remediation to account for most of the improvements observed. Semantic verbal fluency may be the best candidate cognitive endophenotype.

Our results suggest differences between antipsychotics in their effect on the overall cognitive score in schizophrenia. Quetiapine and olanzapine had the most positive effects, followed by risperidone, ziprasidone, amisulpride and haloperidol in that order. Significant differences were also observed according to specific cognitive tasks.