Objective: Bulimia nervosa (BN) is associated with loss-of-control (LOC) eating episodes that frequently occur in response to negative emotions. According to recent neurocomputational models, this link could be explained by a failure to accurately update beliefs about the body in states of high arousal. Specifically, these interoceptive inference models suggest that under-relying on signals from one's body about sensory experience ("low sensory precision") and/or over-relying on previously held beliefs ("excessively precise priors") lead to inaccurate perception and maladaptive behaviors. We conducted an initial test of these core predictions of the interoceptive inference model in BN using self-report measures.
Methods: We compared women with BN (n = 30) and age-, BMI-, and full-scale IQ-matched controls (n = 31) on trust in sensory information from the body and two types of beliefs about what can be done to regulate high negative affect. Within the BN group, we tested interrelations among these measures and explored their associations with LOC eating frequency.
Results: Compared with healthy controls, the BN group reported lower levels of trust in sensory information and stronger beliefs that once upset, there is little one can do, apart from eating, to self-regulate. These beliefs were associated with each other and with lower body trust. Beliefs about the uncontrollability of emotion were associated with more frequent subjective binge-eating episodes.
Conclusions: Findings provide initial support for the core predictions of an interoceptive inference account of BN: low trust in sensory information ("sensory precision") may promote an overreliance on maladaptive "prior beliefs" about the effects of eating on negative emotions, ultimately interfering with accurate updating of beliefs about other strategies that could regulate emotions and maintain LOC eating. Low body trust, strong expectations about emotions, and their neurocomputational underpinnings could be promising combined treatment targets for BN.
Keywords: Bayesian predictive processing; Body trust; Bulimia nervosa; Eating expectancies; Emotion regulation; Interoception; Prior beliefs; Sensory precision.
Interoception, the brain’s processing of bodily signals, is critical for emotional and behavioral control. Disturbances in interoception may contribute to emotion dysregulation and problematic behaviors across a range of psychiatric disorders, including eating disorders, but the exact mechanisms remain unclear. Recent “interoceptive inference” models of psychopathology propose that dysregulated emotions and maladaptive behaviors persist because, during intense emotional states, individuals under-rely on information from bodily signals and over-rely on pre-existing expectations (“prior beliefs”). In this study, we tested these core predictions among individuals with bulimia nervosa (BN). We compared women with BN and healthy controls on self-reported measures of bodily trust and two types of pre-existing beliefs about responses to negative emotions. We found the first evidence of lower trust in bodily signals in individuals with BN compared to controls. This reduced trust was linked to stronger beliefs that there is little one can do, apart from eating, to regulate emotions. These beliefs, in turn, were associated with more frequent eating episodes characterized by loss of control. Though more research is needed to replicate these results, they provide preliminary support for a model that could explain why individuals with BN are more likely to have uncontrolled eating in the context of strong negative emotions.
© 2024. The Author(s).