Background: Treatment of major depression with antidepressants is generally associated
with a delay in onset of clinical response. Functional brain correlates of this phenomenon
have not been previously characterized. Methods: Time course of changes in brain glucose
metabolism were measured using positron emission tomography in hospitalized unipolar
depressed patients treated with fluoxetine. Time-specific and response-specific effects were
examined at 1 and 6 weeks of treatment. Results: Changes were seen over time, and …