Abstract
Background Functional imaging studies of major depressive disorder demonstrate response-specific regional changes following various modes of antidepressant treatment.
Objective To examine changes associated with cognitive behavior therapy (CBT).
Methods Brain changes underlying response to CBT were examined using resting-state fluorine-18–labeled deoxyglucose positron emission tomography. Seventeen unmedicated, unipolar depressed outpatients (mean ± SD age, 41 ± 9 years; mean ± SD initial 17-item Hamilton Depression Rating Scale score, 20 ± 3) were scanned before and after a 15- to 20-session course of outpatient CBT. Whole-brain, voxel-based methods were used to assess response-specific CBT effects. A post hoc comparison to an independent group of 13 paroxetine-treated responders was also performed to interpret the specificity of identified CBT effects.
Results A full course of CBT resulted in significant clinical improvement in the 14 study completers (mean ± SD posttreatment Hamilton Depression Rating Scale score of 6.7 ± 4). Treatment response was associated with significant metabolic changes: increases in hippocampus and dorsal cingulate (Brodmann area [BA] 24) and decreases in dorsal (BA 9/46), ventral (BA 47/11), and medial (BA 9/10/11) frontal cortex. This pattern is distinct from that seen with paroxetine-facilitated clinical recovery where prefrontal increases and hippocampal and subgenual cingulate decreases were seen.