New directions in research on somatic concerns in individuals with eating disorders

Perceptual Dysfunction in Eating Disorders

Eating disorders (EDs) are characterized by abnormal responses to food and weight-related stimuli and are associated with significant distress, impairment, and poor outcomes. Because many of the cardinal symptoms of EDs involve disturbances in perception of one's body or abnormal affective or cognitive reactions to food intake and how that affects one's size, there has been longstanding interest in characterizing alterations in sensory perception among differing ED diagnostic groups. Within the current review, we aimed to critically assess the existing research on exteroceptive and interoceptive perception and how sensory perception may influence ED behavior. Overall, existing research is most consistent regarding alterations in taste, visual, tactile, and gastric-specific interoceptive processing in EDs, with emerging work indicating elevated respiratory and cardiovascular sensitivity. However, this work is far from conclusive, with most studies unable to speak to the precise etiology of observed perceptual differences in these domains and disentangle these effects from affective and cognitive processes observed within EDs. Further, existing knowledge regarding perceptual disturbances in EDs is limited by heterogeneity in methodology, lack of multimodal assessment protocols, and inconsistent attention to different ED diagnoses. We propose several new avenues for improving neurobiology-informed research on sensory processing to generate actionable knowledge that can inform the development of innovative interventions for these serious disorders.

Self-reported interoceptive accuracy and interoceptive attention differentially correspond to measures of visual attention and self-regard

Background

Interoception, the perception of bodily functions and sensations, is a crucial contributor to cognition, emotion, and well-being. However, the relationship between these three processes is not well understood. Further, it is increasingly clear that dimensions of interoception differentially corresponds to these processes, yet this is only recently being explored. The present study addresses two important questions: Are subjective interoceptive accuracy and interoceptive attention related to self-regard and well-being? And are they related to exteroceptive (visual) attention?

Methods

Participants (N = 98; 29% women; aged 23-64 years) completed: a battery of questionnaires to assess subjective accuracy (how well one predicts bodily sensations), interoceptive attention (a tendency to notice bodily signals), self-regard (self-esteem, self-image, life satisfaction), state negative affect (depression, anxiety, and stress), a self-esteem Implicit Association Task (a measure of implicit self-esteem), and a flanker task to assess visual selective attention. Subjective interoceptive accuracy and attention served as dependent variables. Correlations and principal component analysis was used to establish correlations among variables and determine how, or whether, these measures are associated with subjective interoceptive accuracy or attention.

Results

Greater scores on measures of self-regard, implicit self-esteem, cognition and lower negative affect were broadly associated with greater subjective interoceptive accuracy. Conversely, only explicit self-esteem, satisfaction with life, and self-image corresponded to subjective interoceptive attention. An exploratory analysis with a more inclusive scale of interoceptive attention was conducted. Results of this exploratory analysis showed that the broader measure was a stronger correlate to self-regard than subjective interoceptive accuracy, though it, too, did not correlate with visual attention. In short, both subjective interoceptive accuracy and attention corresponded to well-being and mental health, but only accuracy was associated with exteroceptive attention.

Conclusion

These results add to a growing literature suggesting different dimensions of (subjective) interoception differentially correspond to indices of well-being. The links between exteroceptive and interoceptive attention, and their association with merit further study.

The structure of eating disorder and somatic symptoms

Individuals with eating disorders (EDs) often present with somatic concerns in treatment, such as bloating, fullness, and feeling tight clothes on skin. However, most research generally focuses on general interoception (e.g., heartbeat) rather than sensations relevant to EDs (e.g., sensations related to the gastrointestinal system or body movement). In the current study (N = 181), we used network analysis to model the structure of ED symptoms and somatic concerns among individuals with anorexia nervosa, bulimia nervosa, and other specified feeding and eating disorder. Results showed that heightened sensitivity to somatic concerns had the highest strength centrality within a symptom network comprising ED and somatic symptoms. Exploratory graph analysis identified four symptom dimensions: cognitive-affective ED symptoms, behavioral ED symptoms, general interoception, and ED-specific proprioception. Findings suggest that heightened sensitivity to somatic concerns may maintain ED symptoms and mutually reinforce other somatic concerns. Implications concerning assessment and treatment of EDs are discussed.