930. Altered Neural Anticipation of an Aversive Interoceptive Experience in Women Remitted from Bulimia Nervosa
Section snippets
Background
Altered function of the neural circuits supporting body state processing, or interoception, may contribute to bulimia nervosa (BN). However, data suggest both hyper- and hyporesponsivity to interoceptive stimulation in BN. Studies using pleasant stimuli indicate that aberrant signaling during the anticipation or processing of interoceptive events may explain these mixed findings. We examined whether BN is associated with altered activation before, during, and after an unpleasant interoceptive
Methods
Women remitted from BN (RBN; n=19) and control women (CW; n=25) underwent fMRI during an inspiratory breathing load paradigm. T-tests compared group activation in interoceptive search regions of interest (voxel-wise p < 0.01, cluster-wise p < 0.05, corrected). Exploratory Huber robust regressions examined BOLD associations with clinical measures.
Results
During breathing load anticipation, RBN relative to CW showed increased activation in bilateral mid-insula, left superior frontal gyrus (SFG), bilateral putamen, right mid-cingulate, and left posterior cingulate cortex (PCC). Group responses did not differ during or after the breathing load. Increased anticipatory putamen activation was associated with greater reward dependence, and anticipatory activation in SFG, putamen, and PCC was inversely associated with months of bulimic symptom
Conclusions
Hyperactivation during the expectation of an aversive interoceptive experience could represent an exaggerated prediction error signal. This signal may sensitize individuals to changes in interoceptive state and could contribute to or result from repeated binge-eating/purge episodes. Conceptualizing BN as a disorder of aversive interoceptive instability may inform new interventions targeted at regulating interoceptive experiences.
Supported By
R01 MH042984; The Price Foundation
Keywords
Interoception, Bulimia Nervosa, fMRI