Investigating the Causal Role of Prefrontal Control in Decision-making in Patients With Anhedonia

Inclusion Criteria: * Able to provide informed consent * Have normal to corrected vision * Willing to comply with all study procedures and be available for the duration of the study * Speak and understand English * Low suicide risk as determined by the Columbia Suicide Severity Rating Scale (C-SSRS), and by the Hamilton Depression Rating Scale (HAM-D; less than 3 for the suicidality item). * Negative pregnancy test for female participants * Patient Health Questionnaire (PHQ) with 9 items greater than or equal to 10 and a diagnosis of major depressive disorder on the Mini International Neuropsychiatric Interview (MINI) Exclusion Criteria: * Attention deficit (hyperactivity) disorder (currently under treatment) * Neurological disorders and conditions, including, but not limited to: History of epilepsy, seizures (except childhood febrile seizures), dementia, history of stroke, Parkinson's disease, multiple sclerosis, cerebral aneurysm, brain tumors * Medical or neurological illness or treatment for a medical disorder that could interfere with study participation (e.g., unstable cardiac disease, HIV/AIDS, malignancy, liver or renal impairment) * Prior brain surgery * Any brain devices/implants, including cochlear implants and aneurysm clips * History of current traumatic brain injury * (For females) Pregnant or breast feeding * Anything that, in the opinion of the investigator, would place the participant at increased risk or preclude the participant's full compliance with or …