Our findings revealed abnormally elevated lagged phase synchronization within the DMN and between regions of the DMN and FPN in individuals with MDD, which emerged in the beta-band. Although these connectivity disturbances were not evident in those with rMDD (indicating some normalization following remission), variability in lifetime MDE frequency correlated with between-network connectivity across MDD and rMDD groups. Specifically, enhanced DMN-FPN beta-band connectivity was associated with more frequent MDEs since first depression onset, and may therefore be a marker of a more recurrent depressive illness course.
