Rethinking functional connectivity: neural circuits in major depressive disorder revealed by a novel gray-white-gray...

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Traditional studies on major depressive disorder (MDD) focused on gray matter (GM) connectivity, neglecting white matter (WM).
• The gray-white-gray (G-W-G) framework emphasizes WM's role in bridging GM regions for whole-brain communication.

Purpose of the Study:

• To investigate disrupted G-W-G communication connectivity in MDD.
• To explore the clinical relevance of G-W-G connectivity in MDD symptomatology and treatment response.

Main Methods:

• Constructed G-W-G communication framework using resting-state functional magnetic resonance imaging (fMRI) data.
• Analyzed data from 325 MDD patients and 177 healthy controls.

Main Results:

• MDD exhibits disrupted G-W-G communication connectivity, primarily mediated by WM functional disruptions.
• Specific WM tracts (e.g., anterior limb of the internal capsule) linked to suicidal symptoms.
• Certain G-W-G connections show potential for predicting antidepressant treatment efficacy.

Conclusions:

• The G-W-G framework offers novel insights into MDD pathophysiology by integrating GM and WM.
• Disrupted G-W-G neural circuits present potential targets for clinical intervention in MDD.