Multimodal EEG study of emotional face processing in major depressive disorder

Abnormal emotional processing characterizes major depressive disorder (MDD). This multimodal EEG study combines event-related potentials, functional connectivity analysis, and source localization to examine neural mechanisms of emotional face processing, identify neuromodulation targets, and evaluate whether functional connectivity predicts anxiety severity in MDD. Thirty-three participants (16MDD, 17controls) performed an emotional dot-probe task with happy-neutral and sad-neutral face pairs during a 128-channel EEG recording. Analyses encompassed temporal components, functional connectivity, eLORETA source localization, and regression models linking spatial covariance matrices to anxiety scores. Controls exhibited larger P100 amplitudes and longer latencies than MDD patients. Orthogonal envelope correlation analysis revealed significant differences in functional connectivity during emotional face processing between groups. Controls demonstrated stronger Left Middle Temporal Gyrus activation during happy conditions, whereas MDD showed excessive left superior frontal gyrus activation during sad conditions. Early-window functional connectivity optimally predicted anxiety under happy conditions, while mid-window connectivity predicted anxiety under sad conditions. Functional connectivity patterns may serve as biomarkers for anxious depression, with the left middle temporal gyrus and right superior frontal gyrus as potential neuromodulation targets.