Frequency-resolved connectome alterations in major depressive disorder: A multisite resting fMRI study

Area of Science:

• Neuroimaging
• Psychiatry
• Computational Neuroscience

Background:

• Functional connectome studies reveal widespread connectivity alterations in major depressive disorder (MDD).
• Previous research using low-frequency bandpass filtering (0.01-0.08 Hz or 0.01-0.1 Hz) limited understanding of frequency-specific alterations in MDD.
• The impact of frequency on these alterations remains unclear.

Purpose of the Study:

• To investigate frequency-dependent connectome alterations in MDD.
• To analyze resting-state functional MRI data across a wider frequency spectrum.
• To identify specific brain regions and connection types affected by frequency in MDD.

Main Methods:

• Frequency-resolved connectome analyses were performed on a large dataset (1002 MDD patients, 924 controls) from seven independent centers.
• Resting-state functional MRI data were analyzed across three frequency bands: 0.01-0.06 Hz, 0.06-0.16 Hz, and 0.16-0.24 Hz.
• Multisite harmonization was applied to account for site effects.

Main Results:

• Significant frequency-dependent connectome alterations were identified in MDD patients.
• Affected regions include the left inferior parietal, inferior temporal, precentral, fusiform cortices, and bilateral precuneus.
• Alterations primarily involved medium- and long-distance connections and were brain network-dependent. High-frequency alterations in the left precuneus correlated with illness duration.

Conclusions:

• Connectome alterations in MDD are frequency-dependent.
• Analyzing brain connectivity across a wider frequency band provides valuable insights into MDD.
• Further research combining fMRI with physiological recordings is needed to understand high-frequency alterations.