Antipsychotic Therapy and First Episode

Inclusion Criteria: * Male or female patients, from 18 to 65 years of age at Visit 1 * Patients must achieve a level of understanding and expressive capacity sufficient to communicate adequately with the study coordinator and to participate in cognitive testing. * Patients must agree to cooperate with all tests and examinations required by the protocol. They must be willing to comply fully with treatment * Patient must understand the nature of the study and must sign an informed consent document. * Patients must be Cantonese speaking Han Chinese * Patients must be diagnosed, according to the SCID for DSM-IV, with schizophrenia, schizoaffective disorder or schizophreniform psychosis. * Patients must have good response to anti-psychotic treatment by achieving a rating of 2 or below in Clinical Global Impression Scale (CGI) Severity of illness; a rating of 4 or below in Improvement scale, and a rating of 3 or below in (conceptual disorganization, unusual thought content), a rating of 2 or below in (delusion, hallucinatory behavior) and a rating of 4 or below in (Suspiciousness) of Positive and Negative Syndrome Scale (PANSS) for at least 8 weeks Exclusion Criteria: * Female patients who are either pregnant or lactating. * Patients previously on clozapine should be excluded from the study * Significant medical illnesses including seizures. * DSM-IV substance (alcohol or other drugs) abuse or dependence within the past 3 months. * Judged clinically to be at serious suicidal risk. * Treatment with an injectable depot neuroleptic within less than one of the patient's dosing intervals between depot neuroleptic injections prior to study entry.