An insula-based network mediates the relation between rumination and interoceptive sensibility in the healthy population

Background: Individuals sometimes continuously centered their attention on the same thoughts. When such process tends to be negative and self-referential, we delineated this mental state as rumination, which may undermine body's perception of endogenous signal, but little is known about the certainly relationship and the potential neural mechanisms. Methods: Rumination and interoceptive sensibility were measured by questionnaires, then insula-related network of rumination dimensions were examined by the whole brain resting-state functional connectivity (FC) in 479 college students, and whether the insula-based network mediate the relationship between rumination and interoceptive sensibility were tested. Results: Rumination (including brooding reflective pondering) and interoceptive sensibility showed positive correlations. The neural mechanisms of brooding and reflective pondering were all related to the insulanetworks, to be specific, brooding was positively correlated with the FC between the left posterior insula (PI) and left parahippocampal gyrus/ hippocampus (PHG), reflective pondering were positively correlated with the FC between the insula subregion and the dorsolateral prefrontal cortex. Moreover, the relationship between brooding and interoceptive sensibility was mediated by the FC between left PI and left PHG. Limitations: We just tested the relationship between rumination and interoceptive sensibility at a cross-sectional level, but it is unclear that whether the longitudinal relationship would be predicted by the related network. Conclusions: Our findings provided new insights into neural mechanisms of brooding and reflective pondering, also the integration of brooding and interoceptive sensibility. The insula-related networks may contribute crucially to rumination and interoception.