AUTHOR=Xu Zhexue , Zhang Shu , Huang Liyuan , Zhu Xiaolei , Zhao Qing , Zeng Yawei , Zhou Dongfeng , Wang Di , Kuga Hironori , Kamiya Atsushi , Qu Miao 

TITLE=Altered Resting-State Brain Activities in Drug-Naïve Major Depressive Disorder Assessed by fMRI: Associations With Somatic Symptoms Defined by Yin-Yang Theory of the Traditional Chinese Medicine

JOURNAL=Frontiers in Psychiatry

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2018.00195

DOI=10.3389/fpsyt.2018.00195

ISSN=1664-0640

ABSTRACT=<p>Identification of biological markers for defining subtypes of major depressive disorder (MDD) is critical for better understanding MDD pathophysiology and finding effective treatment intervention. The “<italic>Yin</italic> and <italic>Yang</italic>” theory is a fundamental concept of traditional Chinese Medicine (TCM). The theory differentiates MDD patients into two subtypes, <italic>Yin</italic> and <italic>Yang</italic>, based on their somatic symptoms, which had empirically been used for the delivery of effective treatment in East Asia. Nonetheless, neural processes underlying <italic>Yin</italic> and <italic>Yang</italic> types in MDD are poorly understood. In this study, we aim to provide physiological evidence using functional magnetic resonance imaging (fMRI) to identify altered resting-state brain activity associated with <italic>Yin</italic> and <italic>Yang</italic> types in drug-naïve MDD patients. The <italic>Yin</italic> type and <italic>Yang</italic> type MDD patients showed increased amplitude of low-frequency fluctuation (ALFF) in different cortical brain areas in the parietal, temporal, and frontal lobe, compared to matched healthy controls. Differential ALFF is also observed in several cortical areas in frontal lobe and insula between <italic>Yin</italic> and <italic>Yang</italic> type group. Of note, although ALFF is increased in the inferior parietal lobe in both <italic>Yin</italic> and <italic>Yang</italic> type group, inferior parietal lobe-centered functional connectivity (FC) is increased in <italic>Yang</italic> type, but is decreased in <italic>Ying</italic> type, compared with matched healthy controls. These results suggest that differential resting-state brain activity and functional connectivity in <italic>Yin</italic> and <italic>Yang</italic> types may contribute to biological measures for better stratification of heterogeneous MDD patients.</p>