The purpose of this study is to evaluate the efficacy of repetitive transcranial magnetic stimulation in the prevention of relapse of the symptoms of schizoaffective disorder. Primary Outcome Measures:Time between subject randomization to treatment and the first occurrence of a relapse during the Relapse Prevention Period. Secondary Outcome Measures: Symptom change as measured by the Positive and Negative Syndrome Scale (PANSS) total and PANSS factor scores; Illness severity change as measured by Clinical Global Impression of Severity for depression (CGI-S-DEP); Change in subject functioning using the Personal and Social Performance Scale; Change in subject medication satisfaction using the Medication Satisfaction Questionnaire (MSQ).

Schizoaffective disorder is a chronic illness and generally requires life-long treatment. To date however, no physical therapy has been evaluated in the maintenance treatment of schizoaffective disorder. This is a randomized (study drug assigned by chance), double-blind (neither physician nor patient knows the name of the assigned drug), medication-controlled, parallel-group, multicenter study to evaluate the efficacy and safety of repetitive transcranial magnetic stimulation(rTMS), as monotherapy or as an adjunct to antipsychotic, relative to antipsychotic drugs in delaying the time to relapse in patients with schizoaffective disorder. Patients with acute symptoms of schizoaffective disorder will be enrolled. The study will consist of 4 periods: an up to 7 days screening/tolerability period, a 6-week open-label flexible dose lead-in period, a 6-week open-label fixed dose stabilization period, and a 12 months double-blind relapse prevention period. Patients without previous exposure to rTMS will be given 4 to 6 days of rTMS for tolerability testing. Patients can continue their current antipsychotic drugs through Day-1 (the day before the start of the study period). During the open-label periods, all patients will be treated with Risperidone. Patients who meet pre-determined stabilization criteria will be eligible to enter the double-blind relapse prevention period and will be randomly assigned to either receive rTMS or rTMS+Risperidone treatment. Efficacy will be evaluated during the study using a relapse assessment(time between subject randomization to treatment and the first occurrence of a relapse during the Relapse Prevention Period). Secondary Outcome Measures:Secondary Outcome Measures: Symptom change as measured by the Positive and Negative Syndrome Scale (PANSS) total and PANSS factor scores; Illness severity change as measured by Clinical Global Impression of Severity for depression(CGI-S-DEP); Change in subject functioning using the Personal and Social Performance Scale; Change in subject medication satisfaction using the Medication Satisfaction Questionnaire (MSQ). Safety will be assessed throughout the study by monitoring of adverse events, clinical laboratory tests, electrocardiograms (ECGs), vital sign measurements (temperature, pulse, and blood pressure), and weight. A 10 milliliter pharmacogenomic blood sample (sample for DNA research) will be collected from patients who give separate written informed consent for this part of the study.

Inclusion Criteria:

• DSM-IV (Diagnostic and Statistical Manual of Mental Disorders-IV)diagnosis of schizoaffective disorder
• Experiencing an acute exacerbation of psychotic symptoms
• A score of >=4 on at least 3 of the following 7 PANSS items: Delusions (P1), Hallucinatory behavior (P3), Excitement (P4), Hostility (P7), Tension (G4), Uncooperativeness (G8), and Poor Impulse Control (G14)
• A score of >=16 on YMRS and/or a score of >=16 on the HAM-D-21
• Healthy based on physical examinations, electrocardiogram (ECG), laboratory tests, medical history, and vital signs measurements

Exclusion Criteria:

• A primary active mental illness diagnosis other than schizoaffective disorder
• Have attempted suicide within 12 months or are at imminent risk of suicide or violent behavior
• Subjects with first episode of psychosis
• Received electroconvulsive therapy in the past 3 months
• History of hypersensitivity to or intolerance of paliperidone, risperidone, or 20% Intralipid (placebo)
• Received long-acting antipsychotic medication within 2 injection cycles
• Received therapy with clozapine within 3 months
• A history of neuroleptic malignant syndrome
• Previous history of lack of response to antipsychotic medication
• Subjects receiving therapy with antidepressants or mood stabilizers that has been initiated and/or changed in dose <30 days prior to screening
• Receiving therapy with carbamazepine
• Receiving therapy with monoamine oxidase inhibitors
• Pregnant, breast-feeding, or planning to become pregnant

Ages Eligible for Study: 18 Years to 65 Years Genders Eligible for Study: Both Accepts Healthy Volunteers: No