Task-positive and task-negative networks and their relation to depression: EEG beamformer analysis

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Major Depressive Disorder (MDD) is associated with default-mode network (DMN) overactivity, linked to rumination.
• Previous research relied on fMRI, limiting understanding of neural correlates.
• It remains unclear if this DMN/TPN imbalance exists before full-blown MDD.

Purpose of the Study:

• To investigate resting-state network (RSN) connectivity using EEG.
• To determine if DMN predominance over TPN occurs in preclinical stages of depression.
• To explore the neural basis of depressive symptoms in non-clinical samples.

Main Methods:

• Leakage correction applied to beamformer-projected resting EEG.
• Seed-based oscillatory-power envelope correlation analysis used to identify RSNs.
• Beck Depression Inventory (BDI) used to assess depressive symptoms in a non-clinical sample.

Main Results:

• EEG-derived RSNs showed similarity to fMRI findings.
• Depressive symptoms correlated with DMN predominance over TPN in the right insula and temporal lobe (delta band).
• Heightened depressive symptoms associated with stronger DMN-TPN connectivity in emotional circuits.

Conclusions:

• The study confirms neural underpinnings of DMN/TPN imbalance observed in fMRI research.
• Neural mechanisms implicated in depression may be active even in preclinical stages.
• Findings suggest early intervention possibilities for individuals with heightened depressive symptoms.