Unmasking Disease-Specific Cerebral Blood Flow Abnormalities: Mood Challenge in Patients With Remitted Unipolar Depression

Mood challenge in unipolar euthymic patients in full remission unmasks an apparent depression trait marker. The pattern of acute CBF changes is distinct from that seen in euthymic healthy volunteers and mirrors the untreated depressed state seen during a major depressive episode and the pattern of change seen in depressed patients. These findings suggest that disease-specific modifications of pathways mediating transient mood changes are present in unipolar depression independent of clinical illness status. These findings have implications for understanding the vulnerability of remitted patients for illness relapse.