Altered Processing and Integration of Multisensory Bodily Representations and Signals in Eating Disorders: A Possible Path Toward the Understanding of Their Underlying Causes

Abstract

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM V) eating problems are the clinical core of eating disorders (EDs). However, the importance of shape and weight overvaluation symptoms in these disorders underlines the critical role of the experience of the body in the etiology of EDs. This article suggests that the transdiagnostic centrality of these symptoms in individuals with EDs may reflect a deficit in the processing and integration of multisensory bodily representations and signals. Multisensory body integration is a critical cognitive and perceptual process, allowing the individual to protect and extend her/his boundaries at both the homeostatic and psychological levels. To achieve this goal the brain integrates sensory data arriving from real-time multiple sensory modalities and internal bodily information with predictions made using the stored information about the body from conceptual, perceptual, and episodic memory. In this view the emotional, visual, tactile, proprioceptive and interoceptive deficits reported by many authors in individuals with EDs may reflect a broader impairment in multisensory body integration that affects the individual’s abilities: (a) to identify the relevant interoceptive signals that predict potential pleasant (or aversive) consequences; and (b) to modify/correct the autobiographical allocentric (observer view) memories of body related events (self-objectified memories). Based on this view, the article also proposes a strategy, based on new technologies (i.e., virtual reality and brain/body stimulation), for using crossmodal associations to reactivate and correct the multisensory body integration processes.

Increased anticipatory brain response to pleasant touch in women remitted from bulimia nervosa

“…Our findings of altered anticipatory touch signaling in RBN are consistent with Bayesian predictive coding accounts that posit that eating disorders result from a deficit in predictive multisensory body integration, i.e., the ability to integrate multimodal sensory data, internal body information, and predictions from prior body-related experiences 79,80 . According to this model, multisensory bodily representations and signals inform predictions about the causes of sensory events and drive one's behavioral responses to these internal and external sensory events.…”

“…The purpose is to unify these differing bodily signals by reducing prediction errors (or “surprise”) about the expected sensory input, and thus improve accuracy of predictions and plans for coping with them emotionally and behaviorally 81 . The interoceptive deficits observed in individuals with EDs have been hypothesized to reflect a deficit in this multisensory bodily integration that affects the ability to identify and correctly link interoceptive body signals to their potential pleasant or aversive consequences, and to modify stored information of body-related events accordingly 79 , 82 – 84 . This failure to functionally adapt to body-related experiences is thought to contribute to a distorted representation of one’s body, one of the predominant symptoms of eating disorders.…”

From avatars to body swapping: The use of virtual reality for assessing and treating body‐size distortion in individuals with anorexia

“…Interestingly, this variable explained between two and three times more the emergence and maintenance of the disturbances than both dieting and negative affectivity. According to a recent neuroscientific framework (Dakanalis, Gaudio, et al, ; Riva, , ; Riva & Dakanalis, ; Riva & Gaudio, ), this altered experience of the body may reflect a deficit in the processing and integration of multisensory bodily representations that are shaped by top‐down predictive mechanisms (Riva, ; Riva & Dakanalis, ).…”

Do subjects with obesity understimate their body size? A Narrative review of estimation methods and explaining theories

“…An integration to the visual normalization theory comes from Riva and colleagues with the Allocentric Lock Theory - ALT (Dakanalis et al, 2016;Gaudio & Riva, 2013;Riva, 2012Riva, , 2014Riva, , 2017Riva & Dakanalis, 2018;Riva, Gaudio, & Dakanalis, 2014). Every subject grows in a cultural context that provides a prototypical ideal of physical appearance and attractiveness, which participates in the processing of the objectified and social body, two of the six representations that contribute to our bodily experience (Riva, 2017).…”