Electroconvulsive therapy enhances degree centrality in the orbitofrontal cortex in depressive rumination

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Depressive rumination is linked to the onset and persistence of refractory depression.
• Electroconvulsive therapy (ECT) effectively treats refractory depression by altering brain network coordination.
• The precise mechanisms of ECT's effects on depressive rumination are not fully understood.

Purpose of the Study:

• To investigate how electroconvulsive therapy (ECT) affects brain functional connectivity and degree centrality (DC) in patients with refractory depression.
• To explore the relationship between brain network alterations and depressive rumination before and after ECT.
• To identify specific brain regions and networks involved in ECT's modulation of rumination.

Main Methods:

• Degree centrality (DC) and functional connectivity (FC) were analyzed in 32 depression patients (pre- and post-ECT) and 38 healthy controls.
• The Ruminative Response Scale (RRS) measured rumination levels.
• FC was calculated using identified brain regions as seeds, focusing on the default mode network.

Main Results:

• A negative correlation was found between right orbitofrontal cortex (rOFC) DC and brooding pre-ECT and post-ECT.
• rOFC DC increased, while left superior temporal gyrus (lSTG) DC decreased after ECT.
• Patients showed increased FC between rOFC and the default mode network post-ECT.

Conclusions:

• Functional changes in the rOFC and lSTG are associated with ECT's positive effects on depressive rumination.
• ECT may alleviate rumination by modulating the functional coordination of specific brain regions.
• Further research is needed to fully elucidate the neural underpinnings of ECT's efficacy in reducing rumination.