Older adults with depression often also suffer from executive dysfunction—problems with planning, impulse control, and reasoning. Executive dysfunction in older adults predicts poor or delayed response to antidepressant treatment and has been associated with early relapse and recurrence of late-life major depression. Functional magnetic resonance imaging (fMRI) is a scan that can measure the activity of someone's brain while that person performs tasks. So far, no fMRI studies investigating cerebral activation patterns in late-life depression have been published. In this study, people will undergo fMRI while they are performing an executive function task. Older adults with late-life depression and older adults without depression will be tested and compared in order to identify the areas and patterns of brain activity underlying executive dysfunction in late-life depression.