Confirmatory Trial of Gamma Neurofeedback to Improve Working Memory in Schizophrenia

Inclusion Criteria:

* 1\. DSM-5 diagnosis of schizophrenia or schizoaffective disorder, confirmed by the Structured Clinical Interview for DSM-5 (SCID-5) 2. Age 18-55 years 3. Clinically stable: no psychiatric hospitalization in the 3 months prior to enrollment 4. No change in antipsychotic medication type or dosage within 4 weeks prior to baseline assessment 5. Ascertained to be clinically and medically stable by a study investigator 6. Does not meet DSM-5 diagnostic criteria for bipolar disorder or current major depressive episode 7. No electroconvulsive therapy (ECT) within 6 months of baseline assessment 8. Able to read and speak English (corrected vision or hearing aids acceptable) 9. Able and willing to provide written informed consent

Exclusion Criteria:

* 1\. Self-reported history of seizure disorder 2. Diagnosed with multiple sclerosis 3. History of stroke or major vascular disease, including insulin-dependent diabetes mellitus 4. HIV/AIDS diagnosis 5. Current (not past) major depressive episode 6. Substance use disorder other than nicotine use disorder or caffeine use disorder in the past year 7. Brain cancer (primary or metastatic) 8. Prior head injury involving loss of consciousness 9. Inability to read or speak English 10. Color blindness that interferes with administration of study assessments 11. Neuropsychological or cognitive testing in the past 6 months using the same measures as this study 12. Score on Letter-Number Sequencing greater than 1 standard deviation above the age-normed mean