The purpose of this study is to evaluate the potential effects of a cognitive training program when combined with a particular form of psychotherapy (behavioral activation therapy) for depression. Behavioral activation therapy targets changes in behavior as a method for improving a depressed individual's thoughts, feelings, and overall quality of life. This study is designed to test whether a computerized brain exercise called cognitive control training can enhance the effects of a 5-session behavioral activation therapy program. CCT has been shown to reduce depressive symptoms in two other studies, but it has not yet been combined with behavioral activation therapy. The investigators hypothesize that individuals assigned to the behavioral activation plus cognitive control training condition will demonstrate reduced depressive symptoms from pre to post treatment compared with those assigned to the behavioral activation plus computerized control condition. The investigators hypothesize that these gains will be maintained at one-month follow up.

Inclusion Criteria:

1. Adults ages 18-65
2. Primary psychiatric diagnosis of major depressive disorder
3. Ability to read and speak English sufficiently to complete study procedures
4. If taking antidepressant or anxiolytic medication, participants must be taking a stabilized dose for a minimum period of at least 8 weeks prior to entry into the study
5. Willingness and ability to comply with the requirements of the study protocol

Exclusion Criteria:

1. Lifetime history of bipolar disorder or psychotic disorder
2. Neurological disorder such as Parkinson's disease or traumatic brain injury
3. Alcohol or substance dependence within the past 6 months
4. Substantial suicide risk
5. Concurrent psychotherapy initiated within 2 months of baseline, or ongoing psychotherapy of any duration directed specifically toward treatment of the depression other than general supportive therapy
6. Current use of antipsychotics, stimulants, or modafinil