Biosignatures of Latuda for Bipolar Depression

Inclusion Criteria: 1. Age 18- 60 2. Outpatients with a primary Diagnostic and Statistical Manual of the American Psychiatric Association, Fourth Edition (DSM-IV) diagnosis of Bipolar Disorder I, II, or NOS (Not Otherwise Specified) 3. Current episode of Major Depression 4. At least moderate severity of depression 5. Agrees to, and is eligible for, electroencephalogram (EEG) / psychological testing, magnetic resonance imaging (MRI), and blood draws 6. Provides informed consent Exclusion Criteria: 1. Current drug or alcohol abuse/dependence, except nicotine (within 6 months for dependence; 2 for abuse) 2. Taking any of the following exclusionary medications: antipsychotics, anticonvulsants, mood stabilizers, stimulants, antidepressant medications, medications with significant interactions with lurasidone, except during the washout prior to testing and blood collection 3. Unstable medical condition, including significant liver disease, hypothyroidism (i.e., condition not adequately stabilized for 3 months), and conditions likely to require hospitalization or with a life expectancy of \< 6 mos.\* 4. Patients considered at significant risk for suicide 5. Inadequate understanding of English 6. Currently pregnant or breast-feeding; fecund women not using adequate contraceptive methods; plan to become pregnant within 12 months 7. Contraindications to MRI (e.g. ferromagnetic body implants, history of metal working, etc.) 8. Have epilepsy, neuromuscular disorder, or tardive dyskinesia 9. Require immediate hospitalization for psychiatric disorder 10. Require medications for a general medical condition that contraindicate any study medication\*\* 11. Receiving or have received during the index episode vagus nerve stimulation, electroconvulsive therapy, transcranial magnetic stimulation, or other somatic treatments 12. Allergy to, or other medical contraindication to lurasidone treatment 13. Currently enrolled in another research study, and participation in that study contraindicates participation 14. Clinically significant screening laboratory abnormalities (\* see below) 15. Currently taking an effective mood stabilizer and/or antidepressant regimen 16. Inability to undergo a three week medication-free period, including history of significant clinical deterioration from past periods off medication or when medication dosage was reduced, including mania, severe depression, etc. 17. Any reason not listed herein that would make participation in the study hazardous \*Medical criteria for exclusion: * Untreated hypertension: \> 140/90 Torr on repeated measurement (If hypertension becomes stabilized, subject may enroll in study) * Hepatitis: any liver function test \> 2x the upper limit of normal * Renal failure: estimated Glomerular Filtration Rate (eGFR, corrected for body surface area) repeatedly \< 30 mL/min * Hypothyroidism: thryrotropin stimulating hormone level \> upper limit of normal (unless accompanied by other euthyroid indices and the confirmation by an internist or endocrinologist that this does not represent hypothyroidism) * Anemia: hemoglobin \< 10 grams/deciliter (borderline hemoglobin must be of known origin, stable, and not clinically significant)