Altered brain function in treatment-resistant depression patients: A resting-state functional magnetic resonance...

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Treatment-resistant depression (TRD) is associated with known functional brain changes.
• Previous functional connectivity (FC) studies often relied on predefined regions of interest.
• Combining amplitude of low-frequency fluctuation (ALFF) with FC offers a novel approach to investigate TRD's neural basis.

Purpose of the Study:

• To explore alterations in brain activity using ALFF in TRD patients.
• To investigate functional connectivity (FC) changes in TRD by using ALFF-identified regions as seeds.
• To correlate brain activity with clinical symptom severity in TRD.

Main Methods:

• 16 TRD patients and 16 healthy controls underwent resting-state functional magnetic resonance imaging (fMRI).
• ALFF was analyzed at baseline to identify regions with altered activity in TRD.
• Seed-based FC analysis was performed on identified regions, and correlations with PDQ-5D scores were calculated.

Main Results:

• TRD patients exhibited significantly decreased or increased ALFF in the postcentral gyrus and cuneus compared to controls.
• ALFF in the right hippocampus negatively correlated with PDQ-5D scores in TRD patients.
• Abnormal FC was observed in the middle frontal gyrus, inferior frontal gyrus, anterior cingulate cortex, supramarginal gyrus, and calcarine cortex.

Conclusions:

• TRD patients display widespread alterations in brain regions involved in the central executive network (CEN), salience network (SN), and default mode network (DMN).
• The combined ALFF and FC approach reveals a broader spectrum of neural dysfunction in TRD than previously identified.