Disrupted subsystem interactions of default mode network in mild cognitive impairment: A Resting-State Functional Connectivity MRI Study

The default mode network (DMN) could be further divided into three subsystems, and each subsystem of DMN serves different cognitive functions. In this study, we revealed that cognitive decline is driven by weakened functional connectivity within the core subsystems, but enhanced functional connectivity between the core and MTL subsystems as well as the core and DMPFC subsystems. This dissociation may reflect abnormal core-centered connection abnormalities, along with the disruption of the MTL subsystem and the DMPFC subsystem to some degree. Our findings provided a promising imaging biomarker for the early diagnosis of AD.