Early-Stage Psychotherapy Produces Elevated Frontal White Matter Integrity in Adult Major Depressive Disorder

Abstract

BackgroundPsychotherapy has demonstrated comparable efficacy to antidepressant medication in the treatment of major depressive disorder. Metabolic alterations in the MDD state and in response to treatment have been detected by functional imaging methods, but the underlying white matter microstructural changes remain unknown. The goal of this study is to apply diffusion tensor imaging techniques to investigate psychotherapy-specific responses in the white matter.MethodsTwenty-one of forty-five outpatients diagnosed with major depression underwent diffusion tensor imaging before and after a four-week course of guided imagery psychotherapy. We compared fractional anisotropy in depressed patients (n = 21) with healthy controls (n = 22), and before-after treatment, using whole brain voxel-wise analysis.ResultsPost-treatment, depressed subjects showed a significant reduction in the 17-item Hamilton Depression Rating Scale. As compared to healthy controls, depressed subjects demonstrated significantly increased fractional anisotropy in the right thalamus. Psychopathological changes did not recover post-treatment, but a novel region of increased fractional anisotropy was discovered in the frontal lobe.ConclusionsAt an early stage of psychotherapy, higher fractional anisotropy was detected in the frontal emotional regulation-associated region. This finding reveals that psychotherapy may induce white matter changes in the frontal lobe. This remodeling of frontal connections within mood regulation networks positively contributes to the “top-down” mechanism of psychotherapy.

Microstructural brain abnormalities in medication-free patients with major depressive disorder: a systematic review and meta-analysis of diffusion tensor imaging

“…The subgroup analysis of studies with corrected results included 10 data sets 13,22,[25][26][27][28][41][42][43][44] comprising 344 patients with MDD and 338 healthy controls. These results were consistent with the pooled meta-analysis (Table 3), showing few effects of uncorrected results on the overall conclusions.…”

“…The medication washout subgroup analysis included 8 data sets 13,22,24,25,27,30,41,44 that compared 260 patients with MDD and 272 healthy controls. Fractional anisotropy reductions were identified in the white matter of the right cerebellum hemispheric lobule, body of the CC, bilateral SLF III and the long segment of the arcuate network (Table 3 and Appendix 1, Fig.…”

“…70 As we know, MDD has traditionally been viewed as an affective disorder characterized by strong feelings of sadness, guilt, worthlessness and hopelessness. 13,15,25,43 Furthermore, studies have shown that MDD is associated with significant disturbances in cognitive functioning, including executive functions, attention, memory and psychomotor speed. 13,30,43,71 Some investigations have provided evidence for the hypothesis that the cerebellum is an essential node in the distributed neural circuitry subserving cognitive and affective functions.…”

“…Tract-based spatial statistics (TBSS) isolates the central core of white matter tracts with the highest FA and reports significant clusters within that white matter skeleton. 21 Results from whole-brain studies have suggested widespread white matter abnormalities in MDD in regions such as the frontal gyrus, 15,22,23 cerebellum, 22,24,25 right thalamus, 24,25 right parietal lobe, 22,23 corpus callosum (CC) 26,27 and superior longitudinal fasciculus (SLF). [28][29][30] However, these results are not consistent, probably owing to small or heterogeneous study samples and methodological differences.…”

Diagnostic and therapeutic utility of neuroimaging in depression: an overview

“…To date, only one study has examined the effect of psychological therapy on white matter integrity 106. It found that after 4 weeks of guided imagery therapy, FA was increased in the supplementary motor area and decreased in the angular gyrus.…”