The purpose of this study is to further characterize the neural correlates of affective processing in BD and MDD subjects using fMRI. Subjects who meet criteria for a major depressive episode in the context of BD (n=15); MDD (n=15) and a group of psychiatrically unaffected control subjects (CS, n=15) will undergo four fMRI scans while experiencing a temporary mood induction through the presentation of affective imagery from the International Affective Picture System (IAPS). Both BD and MDD subjects will receive the same combination pharmacotherapy to treat the depression, with fMRI data acquired before, and 1, 3, 6 weeks following pharmacotherapy initiation. Positive, negative, and neutral affective visual stimuli will be presented in a blocked design.
Comparison(s): The effects of time and group will be analyzed in factorial models. Regions of interest that demonstrate significant group-by-time interactions will be further correlated with self-report and clinician-rated psychometric indices.
