Dissociation of regional activity in the default mode network in first-episode, drug-naive major depressive disorder at rest.
BACKGROUND
Major depressive disorder (MDD) is associated with altered neural activity in the default mode network (DMN). In the present study, we used a fractional amplitude of low-frequency fluctuations (fALFF) approach to directly investigate the features of spontaneous brain activity of the DMN in patients with the first-episode, drug-naive MDD at rest.


METHODS
Twenty-four first-episode, drug-naive patients with MDD and 24 age-, gender-, and education-matched healthy subjects participated in the study. The fALFF and independent component analysis (ICA) approaches were utilized to analyze the data.


RESULTS
Patients with MDD exhibited a dissociation pattern of resting-state fALFF in the DMN, with increased fALFF in the left dorsal medial prefrontal cortex (MPFC) and decreased fALFF in the left parahippocampal gyrus (PHG). The increased fALFF values of the left dorsal MPFC were positively correlated to the Hamilton Rating Scale for Depression (HRSD) scores.


CONCLUSIONS
Our results first suggested that there was a dissociation pattern of resting-state fALFF in the DMN in patient with MDD, which highlighted the importance of the DMN in the pathogenesis of MDD.
Mental Health Center, the First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi 530021, China. Electronic address: guowenbin76@163.com.
Wenbin
W
Guo
Feng
F
Liu
Jian
J
Zhang
Zhikun
Z
Zhang
Liuyu
L
Yu
Jianrong
J
Liu
Huafu
H
Chen
Changqing
C
Xiao
D000328:Adult; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000503:physiopathology*; D005260:Female; D059907:Functional Neuroimaging / Q000379:methods; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009415:Nerve Net / Q000503:physiopathology*; D020534:Parahippocampal Gyrus / Q000503:physiopathology*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D012146:Rest / Q000502:physiology; D055815:Young Adult
Default mode network; Fractional amplitude of low-frequency fluctuations; Independent component analysis; Major depressive disorder