Photobiomodulation to Alter Cerebral Blood Flow and to Affect the Emotional Status of Patients With Major Depression

Inclusion Criteria: * All patients must be right handed, between the ages of 18 and 60, and meet criterion for depression on a Structured Clinical Diagnostic Interview * Enrollment will be made without regard to gender or ethnicity * Patients who are receiving treatment for depression, either psychological or pharmacological, may continue their treatment during the time of the study, but will be asked to try not to alter their treatment from one month prior to the onset of the experiment until its conclusion. If they must alter their treatment, the patient will continue in the study for observation, but will be excluded from any follow-up statistical comparisons Exclusion Criteria: * Past history of psychotic disorder (including schizophrenia or schizoaffective disorder * Bipolar disorder * Obsessive compulsive disorder) * Substance abuse disorder that has been active with the past 6 months, * A history of violent behavior * A history of a past suicide gesture or attempt * A history of current suicidal ideation * A history of a neurological condition (e.g. epilepsy, traumatic brain injury, stroke) * Pregnancy * Current acute or chronic medical condition requiring a medications that has psychological side-effects * Any person whom we judge to have an impaired decision-making capacity