Amygdala Neurofeedback for Depression - Large Scale Clinical Trial

Inclusion Criteria: * ages 18 - 55 * primary diagnosis of MDD and are currently depressed * able to give written informed consent prior to participation * unmedicated OR are stable on an antidepressant regime (at least 4 weeks to ensure symptoms are stable). Effective medications will not be discontinued for the purposes of the study. Exclusion Criteria: * clinically significant or unstable cardiovascular, pulmonary, endocrine, neurological, gastrointestinal illness or unstable medical disorder * Current severe DSM-V alcohol or substance use disorder, with the exception of nicotine or caffeine. Clinician will access subjects' alcohol and substance use on a case-by-case to determine whether specific cases of mild or moderate alcohol or substance use would also interfere with the effects of the intervention. * history of traumatic brain injury * unable to complete MRI scan due to claustrophobia or general MRI exclusions (e.g., shrapnel inside body) * currently pregnant or breast feeding * unable to complete questionnaires written in English * current (within 3 weeks of testing) use of any antipsychotics, anticonvulsants, stimulants, benzodiazepines, beta-blockers, or other medications (except antidepressants) likely to influence cerebral blood flow. Effective medications will not be discontinued for the purposes of the study. * diagnosis of psychotic or organic mental disorder, bipolar I or II disorder. * eye problems or difficulties in corrected vision.