Cardiac interoceptive processing and emotional experience in binge eating behavior: Neural evidence of disengagement from bodily sensations.

Objective: This study provides a comprehensive assessment of cardiac interoception in individuals with binge eating (BE) behavior and compares their emotional experience and affective state related to heartbeat perception with those of healthy controls (HCs).

Method: After a 5-min resting phase, participants (n = 28 BE group, n = 28 HC group) completed the heartbeat counting task, with concurrent EEG and ECG recording. Indices for interoceptive accuracy (IAcc), interoceptive beliefs (IBe), and interoceptive insight (IIn) were computed. Heart rate (HR) and heart rate variability (HRV) served as indicators of bodily signal strength. Heartbeat-evoked potentials (HEPs) were derived to assess the neural representation of cardio-afferent signals at the cortical level during rest or task performance. Emotional experiences and changes in affective state from pre-to post-task were assessed using self-reports.

Results: The BE group exhibited lower mean HR and higher HRV compared to HCs. No group differences were found in IAcc, IBe, or IIn. HCs showed increased HEP amplitudes during the task compared to rest, whereas no such effect was observed in the BE group. Both groups reported an increase in negative affect from pre-to post-task, with the BE group experiencing significantly higher negative affect post-task.

Discussion: The altered neural representation observed in the BE group may reflect disengagement from bodily sensations, which may impair emotion processing and regulation, potentially contributing to BE behavior. Further research is warranted to determine whether this pattern is specific BE-related eating disorders (EDs) or relevant to EDs in general.