Intrinsic inter-network brain dysfunction correlates with symptom dimensions in late-life depression.

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Late-life depression (LLD) is associated with neurocognitive network dysfunctions.
• Previous research focused on intra-network deficits, leaving inter-network connectivity in LLD largely unexplored.
• The relationship between these network disruptions and core LLD symptom dimensions remains unclear.

Purpose of the Study:

• To investigate inter-network functional connectivity in LLD using resting-state fMRI.
• To determine if altered inter-network connectivity in LLD is associated with depression, anxiety, and executive dysfunction.
• To explore the potential of inter-network connectivity as neuroimaging biomarkers for LLD.

Main Methods:

• Cross-sectional resting-state functional connectivity MRI study.
• Involved 39 LLD participants and 29 healthy comparison (HC) participants.
• Utilized dual regression independent component analysis to analyze executive control (ECN), default mode (DMN), and salience (SN) networks.

Main Results:

• LLD patients exhibited decreased connectivity between the ECN and subcortical DMN regions, and between the ECN and SN insula.
• Increased connectivity was observed between the left ECN and posterior DMN/SN components in LLD.
• Abnormal inter-network connectivity correlated significantly with depression, anxiety, and executive dysfunction severity.

Conclusions:

• Inter-network connectivity abnormalities are present in LLD and linked to core symptom dimensions.
• These findings suggest a mechanistic framework for understanding LLD's neural basis.
• Inter-network connectivity may serve as neuroimaging biomarkers for LLD symptom dimensions, aiding targeted treatments.