The subsystem mechanism of default mode network underlying rumination: A reproducible neuroimaging study

NeuroImage

Zhen Fan¹  Hui-Xian Li¹  Bin Lu²  Ning-Xuan Chen²  Zhi-Chen Zhu³  Yang-Qian Shen³  Xiao Chen⁴  Le Li⁴  Chao-Gan Yan⁵ 

[1] Department of Psychology, University of Chinese Academy of Sciences, Beijing, 100049, China;International Big-Data Center for Depression Research, Institute of Psychology, Chinese Academy of Sciences, Beijing, 100101, China;Magnetic Resonance Imaging Research Center, Institute of Psychology, Chinese Academy of Sciences, Beijing, 100101, China;CAS Key Laboratory of Behavioral Science, Institute of Psychology, Beijing 100101, China;Graduate School of Education, Fordham University, New York, NY, 10023, United States;

关键词: Functional mri;    Rumination;    Self-generated thought;    Default mode network;   

DOI  :  

来源: DOAJ

【 摘 要 】

Rumination is a repetitive self-referential thinking style that is often interpreted as an expression of abnormalities of the default mode network (DMN) observed during “resting-state” in major depressive disorder (MDD). Recent evidence has demonstrated that the DMN is not unitary but can be further divided into 3 functionally heterogenous subsystems, although the subsystem mechanistically underlying rumination remains unclear. Due to the unconstrained and indirect correlational nature of previous resting-state fMRI studies on rumination's network underpinnings, a paradigm allowing direct investigation of network interactions during active rumination is needed. Here, with a modified continuous state-like paradigm, we induced healthy participants to ruminate or imagine objective scenarios (distraction, as a control condition) on 3 different MRI scanners. We compared functional connectivities (FC) of the DMN and its 3 subsystems between rumination and distraction states. Results yielded a highly reproducible and dissociated pattern. During rumination, within-DMN FC was generally decreased as compared to the distraction state. At the subsystem level, we found increased FC between the core and medial temporal lobe (MTL) subsystem as well as decreased FC between the core and dorsal medial prefrontal cortex (DMPFC) subsystem and within the MTL subsystem. Finally, subjects’ behavioral measures of rumination and brooding were negatively correlated with FC between the core and DMPFC subsystems. These results suggest active rumination involves enhanced constraint by the core subsystem on the MTL subsystem and decreased coupling between the core and DMPFC subsystem, allowing for more information exchange among those involved DMN components. Furthermore, the reproducibility of our findings provides a rigorous evaluation of their validity and significance.

【 授权许可】

Unknown