RISPERIDONE VS. HALOPERIDOL ON REACTION-TIME, MANUAL DEXTERITY, AND MOTOR LEARNING IN TREATMENT-RESISTANT SCHIZOPHRENIA-PATIENTS

Background: The present study compared the effects of risperidone vs. haloperidol on reaction time, manual dexterity, and two types of motor learning in a sample of treatment-resistant schizophrenia patients. M ethods: Fifty-six DSM-III-R diagnosed schizophrenia inpatients partici pated in a randomized double-blind comparison of risperidone vs. halop eridol, Measures of reaction rime, manual dexterity, motor sequence le arning and gross motor learning were administered at baseline, after 4 weeks of fixed-dose medication, and after 4 weeks of flexible-dose me dication. Results: The results indicated that patients receiving rispe ridone showed greater improvement in reaction time and manual dexterit y than patients receiving haloperidol. After covarying symptom changes and movement disorder ratings, the results remained significant. The two treatment groups did not differ on either measure of motor learnin g. Conclusions: The differences in performance in reaction rime and ma nual dexterity may be due to a specific beneficial effect of risperido ne, as opposed to a general reduction in extrapyramidal symptom liabil ity, compared to haloperidol. Biol Psychiatry 1998;44: 726-732 Publish ed 1998 Society of Biological Psychiatry.