Habenular Involvement in Response to Subcallosal Cingulate Deep Brain Stimulation for Depression.

Area of Science:

• Neuroscience
• Neuroimaging
• Psychiatry

Background:

• The habenula (Hb) is an epithalamic structure involved in reward and mood regulation.
• Previous imaging studies suggest Hb structure and function relate to mood disorder treatment response.
• Subcallosal cingulate area deep brain stimulation (SCC-DBS) is used for treatment-resistant mood disorders.

Purpose of the Study:

• To investigate the habenula's role in treatment response to SCC-DBS for mood disorders.
• To examine longitudinal changes in Hb volume and functional connectivity following SCC-DBS.

Main Methods:

• Multimodal MRI techniques, including automated segmentation and functional MRI (fMRI).
• Comparison of Hb volume at baseline and post-surgery in 32 patients receiving SCC-DBS.
• fMRI analysis of Hb functional connectivity changes during active SCC-DBS in 12 patients.

Main Results:

• Responders to SCC-DBS showed increased Hb volume over time, while non-responders showed decreased volume (t = 2.4, p = 0.021).
• Active SCC-DBS significantly increased Hb functional connectivity to prefrontal and corticolimbic regions (TFCE-adjusted p < 0.0001).
• These connected regions are implicated in the neurocircuitry of depression.

Conclusions:

• The habenula plays a significant role in the antidepressant effects of SCC-DBS.
• Longitudinal Hb volume changes and altered functional connectivity are associated with treatment response.
• Findings highlight the habenula as a potential target for mood disorder interventions.