AUTHOR=Shan Qinfan , Wu Guisen , Xiong Yuxuan , Guo Qian , Hu Hao , Zhang Fuxu , Qian Zhenying , Zhang Tianhong , Liu Xiaohua 
  
TITLE=Altered EEG microstate associated with anxiety and somatization symptoms in major depressive disorder
  
JOURNAL=Frontiers in Psychiatry
  
VOLUME=Volume 17 - 2026
  
YEAR=2026
  
URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2026.1772171
  
DOI=10.3389/fpsyt.2026.1772171
  
ISSN=1664-0640
  
ABSTRACT=ObjectiveTo examine abnormalities in EEG microstate dynamics in patients with major depressive disorder (MDD) and to explore their associations with anxiety and somatization symptoms.MethodsWe enrolled 30 patients with MDD and 40 healthy controls. Resting-state EEG was recorded and analyzed using microstate segmentation (classes A–D). Temporal parameters (mean duration, occurrence, time coverage, and transition probabilities) were compared between groups, and correlations with clinical symptoms (HAMD, HAMA, MADRS) were examined.ResultsCompared with controls, patients with MDD exhibited a significantly longer duration, higher occurrence, and greater time coverage of microstate C, while microstate B showed reduced occurrence and coverage. Transition probability analyses revealed fewer transitions from A to B, A to D, B to A, B to D, and D to A, and more transitions between C and D. Symptom correlations indicated that microstate B occurrence was positively associated with HAMD anxiety/somatization scores, while transitions from C to D and from D to C were negatively correlated with anxiety/somatization scores.ConclusionsMDD is characterized by alterations in microstate B and C dynamics and disrupted transitions between C and D, some of which relate to symptom dimensions, suggesting that EEG microstate features may serve as potential neurophysiological markers in major depressive disorder.