Commonalities and differences in ECT-induced gray matter volume change between depression and schizophrenia

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Electroconvulsive therapy (ECT) is a highly effective treatment for severe depression and schizophrenia.
• Previous studies show ECT increases regional gray matter volume (GMV), but the interpretation is complex.
• It's unclear if GMV changes are treatment-specific or due to the intervention itself.

Purpose of the Study:

• To differentiate between diagnosis-specific and transdiagnostic GMV changes after ECT.
• To investigate if GMV changes correlate with clinical improvement in depression and schizophrenia.

Main Methods:

• Longitudinal magnetic resonance imaging (MRI) and voxel-based morphometry were used.
• 29 Japanese participants (18 with major depressive disorder, 11 with schizophrenia) were studied before and after ECT.
• GMV changes were analyzed for commonalities and differences between the two groups.

Main Results:

• Both depression and schizophrenia patients showed widespread GMV increases post-ECT.
• Common increased GMV regions included the anterior temporal cortex, medial frontal cortex, anterior cingulate cortex, insula, and caudate nucleus.
• Schizophrenia patients exhibited a specific GMV increase in the left pregenual anterior cingulate cortex, correlating with clinical improvement.

Conclusions:

• Transdiagnostic GMV changes likely reflect ECT's general effects and shared pathophysiology.
• Diagnosis-specific GMV changes, like in schizophrenia, may be linked to treatment efficacy and condition-specific pathophysiology.
• These findings help distinguish ECT's direct effects from its therapeutic impact on specific disorders.