Disrupted brain network dynamics and cognitive dysfunction in drug-naive major depressive disorder: an EEG microstate...

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Science

Background:

• Brain network dysfunctions are implicated in emotional disorders.
• Limited research exists on resting-state EEG brain networks and cognitive function in Major Depressive Disorder (MDD).

Purpose of the Study:

• To investigate aberrant brain network activity using EEG microstates in MDD patients.
• To explore the relationship between altered brain network dynamics and cognitive performance in MDD.
• To elucidate the neuropathological mechanisms underlying MDD.

Main Methods:

• Utilized 64-channel resting-state EEG to capture brain activity in 68 drug-naïve MDD individuals and 50 healthy controls (HCs).
• Assessed cognitive functions using Trail Making Test (TMT), Symbol Digit Modalities Test (SDMT), and Stroop Color-Word Test (SCWT).
• Analyzed EEG microstate topographies, coverage, duration, and occurrence, employing Pearson correlation to link network dynamics with cognitive performance in MDD.

Main Results:

• Identified four distinct EEG microstate maps.
• MDD patients showed significantly reduced coverage, duration, and occurrence of microstates A and D, and increased microstate B compared to HCs.
• MDD patients performed significantly lower on cognitive tests (TMT, SDMT, SCWT) than HCs.
• Microstate A parameters negatively correlated with Stroop test performance, while microstate D correlated positively with SDMT scores in MDD patients.

Conclusions:

• Individuals with MDD exhibit aberrant EEG microstate dynamics.
• Alterations in microstate activity are significantly associated with cognitive deficits in MDD.
• Findings support the link between disturbed brain network dynamics and cognitive dysfunction in MDD, offering potential neuropathological insights.