Effects of Intranasal Insulin on Neuroimaging Markers and Cognition in Patients With Psychotic Disorders

Inclusion Criteria: * Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnoses of schizophrenia, schizoaffective disorder or bipolar disorder with psychotic features OR * Healthy Controls (no history of DSM psychiatric diagnoses, nor history of the same in first-degree relatives) Exclusion Criteria: * Psychiatric hospitalization within the last 4 weeks * Unstable/active disease or potential contraindications, such as liver disease, kidney disease, uncontrolled hypertension, significant or unstable medical illness * Currently prescribed: antidiabetic agents, including oral antidiabetic medications and insulin, intranasal medication, steroids, weight loss agents * Pregnant or breast-feeding, not using an effective form of contraception for at least 3 months, and/or not abstinent for 1 month prior to enrollment * History of significant head injury * Contraindication to MRI scans (claustrophobia, cardiac pacemakers, metal clips and stents on blood vessels, artificial heart valves, artificial arms, hands, legs, etc., brain stimulator devices, implanted drug pumps, ear implants, eye implants or known metal fragments in eyes, exposure to shrapnel or metal filings, other metallic surgical hardware in vital areas, certain tattoos with metallic ink, certain transdermal patches, metal-containing IUDs). * Medical conditions preventing blood draws * History of electroconvulsive therapy (ECT) or transcranial magnetic stimulation (TMS) within the last 3 months * BMI \> 35 or body weight \> 350 lbs or BMI \<18 * DSM diagnosis of substance use disorder in the past month * For Healthy Controls: * Taking medication other than birth control