Autonomic and resting-state effective connectivity signatures of binge eating behavior

Autonomic dysfunction, measured by heart rate variability (HRV) is implicated in the manifestation of binge eating (BE) behaviors. Aberrant resting-state functional connectivity among brain regions involved in reward processing, affect regulation, and cognitive control have been implicated in BE. However, the co-influence of brain regions involved in central autonomic control and BE behavior remains unclear. The current study examines whether effective connectivity (EC) patterns in neural networks supporting the afore-mentioned motivational, emotional, and cognitive processes moderates the relationship between HRV and BE behaviors. Resting-state fMRI data from an a priori-defined eating regulation network was analyzed in 158 healthy adults (BE = 30; Control = 128) using spectral dynamic causal modeling. Leave-one-out cross-validation (LOOCV) evaluated the predictive utility of EC patterns on BE group status. Although 20 EC connections were associated with BE (posterior probability > 0.99), EC from the left posterior cingulate cortex to the hypothalamus predicted group membership above chance (AUC = 0.622, 95% CI [0.508, 0.731]). Approximate entropy was a significant predictor of binge eating behavior (ß = -6.625; p < 0.05) in a subset of 114 participants with usable photoplethysmography data (BE = 24; Control = 90). This relationship was significantly moderated by ventral tegmental area to hypothalamus EC (ß = -6.529; p < 0.05). These findings uncover novel directional information flow from brain regions involved in reward processing and emotion regulation to those involved in food-seeking behavior is mitigated by autonomic tone, offering promising targets for future intervention strategies for BE.