Body image in anorexia nervosa: the link between functional connectivity alterations and spatial reference frames

Psychotic-like anomalous self-experiences in feeding and eating disorders: Their role in eating psychopathology through the mediation of body uneasiness and embodiment and identity disorders

BACKGROUND

Psychotic-like anomalous self-experiences (ASEs) are core and early features of schizophrenia spectrum disorders, which have been recently also postulated to underlie embodiment disturbance in feeding and eating disorders (FEDs). The present study was aimed at investigating the interplay between ASEs and specific psychopathology in FED.

METHODS

Ninety persons with Anorexia Nervosa and 41 with Bulimia Nervosa were evaluated with the inventory of psychotic-like anomalous self-experiences (IPASE), identity and eating disorders (IDEA), body uneasiness test (BUT), and eating disorder examination questionnaire (EDE-Q). The same assessment was performed for 92 subjects recruited from the general population. Structural equation modelling was employed to test the role of embodiment/identity disorders in mediating the relationship between ASEs and ED psychopathology.

RESULTS

Patients with FED displayed high scores on IPASE, comparable with people with schizophrenia spectrum disorders. A significant correlation was also demonstrated between IPASE, BUT and EDE-Q. All IPASE domains were strongly related to feeling extraneous from one's own body by IDEA. All IPASE domains demonstrated a high relationship with BUT Depersonalization scale. A strong correlation was also reported between total scores of IPASE and IDEA. The mediation model confirmed that ASEs impact on FED symptomatology through the mediation of both embodiment/identity disorders and body image.

DISCUSSION

Anomalous interoceptive processes may represent the first step of a maladaptive process-impairing embodiment, selfhood, and identity in FED. Assessment of ASEs might be a valid tool to identify an early-shared vulnerability of severe disorders characterized by embodiment alterations.

Central Autonomic Network Alterations in Anorexia Nervosa Following Peripheral Adrenergic Stimulation

BACKGROUND

Anorexia nervosa (AN) is characterized by low body weight, disturbed eating, body image disturbance, anxiety, and interoceptive dysfunction. However, the neural processes underlying these dysfunctions in AN are unclear. This investigation combined an interoceptive pharmacological probe, the peripheral β-adrenergic agonist isoproterenol, with resting-state functional magnetic resonance imaging to examine whether individuals with AN relative to healthy comparison participants show dysregulated neural coupling in central autonomic network brain regions.

METHODS

Resting-state functional magnetic resonance imaging was performed in 23 weight-restored female participants with AN and 23 age- and body mass index-matched healthy comparison participants before and after receiving isoproterenol infusions. Whole-brain functional connectivity (FC) changes were examined using central autonomic network seeds in the amygdala, anterior insular cortex, posterior cingulate cortex, and ventromedial prefrontal cortex after performing physiological noise correction procedures.

RESULTS

Relative to healthy comparison participants, adrenergic stimulation caused widespread FC reductions in the AN group between central autonomic network regions and motor, premotor, frontal, parietal, and visual brain regions. Across both groups, these FC changes were inversely associated with trait anxiety (State-Trait Anxiety Inventory-Trait), trait depression (9-item Patient Health Questionnaire), and negative body image perception (Body Shape Questionnaire) measures, but not with changes in resting heart rate. These results were not accounted for by baseline group FC differences.

CONCLUSIONS

Weight-restored females with AN show a widespread state-dependent disruption of signaling between central autonomic, frontoparietal, and sensorimotor brain networks that facilitate interoceptive representation and visceromotor regulation. Additionally, trait associations between central autonomic network regions and these other brain networks suggest that dysfunctional processing of interoceptive signaling may contribute to affective and body image disturbance in AN.

Body Image, Social Physique Anxiety Levels and Self-Esteem among Adults Participating in Physical Activity Programs

(1) Background: individuals may benefit from being involved in physical and athletic activities in order to improve their body appearance and promote their physical and mental health. This study aimed to investigate body image, body mass index (BMI) characteristics, social physique anxiety, self-esteem and possible correlations between the above factors. (2) Methods: 245 adults engaged in training programs in gyms, as well as in track and field, football and basketball athletic activities completed (a) a sociodemographic questionnaire which recorded their BMI values and utilized the (b) Body-Esteem Scale for Adolescents and Adults, (c) the Social Physique Anxiety Scale and (d) the Rosenberg Self-Esteem Scale. (3) Results: Females and individuals with higher BMI reported statistically significant lower body-esteem and greater social physique anxiety levels compared to males and individuals with lower BMI, respectively (p < 0.05). A total of 25.3% of our participants were labeled as "overweight", while 20.4% had been overweight in the past. Significant differences were reported between body-esteem and social physique anxiety levels (p < 0.001); age (p = 0.001); BMI value (p < 0.001) and never having a problem with body weight (p = 0.008). Additionally, individuals with lower body-esteem and greater social physique anxiety levels presented lower global self-esteem (p < 0.001). (4) Conclusions: individuals' engagement in physical activity promotes physical as well as mental well-being, contributing to an improved quality of life, which may be the most important issue for health care professionals.

eLoriCorps Immersive Body Rating Scale and eLoriCorps Mobile Versions: Validation to Assess Body Image Disturbances from Allocentric and Egocentric Perspectives in a Nonclinical Sample of Adolescents

A growing number of studies have used virtual reality (VR) for the assessment and treatment of body image disturbances (BIDs). This study, conducted in a community sample of adolescents, documents the convergent and discriminant validity between (a) the traditional paper-based Figure Rating Scale (paper-based FRS), (b) the VR-based Body Rating Scale (eLoriCorps-IBRS 1.1), and (c) the mobile app-based Body Rating Scale (eLoriCorps-IBRS 1.1-Mobile). A total of 93 adolescents (14 to 18 years old) participated in the study. Body dissatisfaction and body distortion were assessed through the paper-based FRS, the eLoriCorps-IBRS 1.1 and the eLoriCorps-IBRS 1.1-Mobile. Eating disorder symptoms, body image avoidance, and social physique anxiety were also measured. Correlation analyses were performed. Overall, the results showed a good and statistically significant convergence between allocentric perspectives as measured by the paper-based FRS, the eLoriCorps-IBRS 1.1 and the eLoriCorps-IBRS 1.1-Mobile. As expected, the egocentric perspective measured in VR produced different results from the allocentric perspective, and from cognitive–attitudinal–affective dimensions of BIDs, with the exception of body distortion. These differences support the discriminant validity of the egocentric perspective of eLoriCorps-IBRS 1.1 and are consistent with emerging evidence, highlighting a difference between experiencing the body from an egocentric (i.e., the body as a subject) and allocentric (i.e., the body as an object) perspective. The egocentric perspective could reflect a perceptual–sensory–affective construction of BIDs, whereas allocentric measures seem to be more related to a cognitive–affective–attitudinal construction of BIDs. Moreover, the results support the validity of the eLoriCorps-IBRS 1.1-Mobile with promising perspectives of implementation among young populations.

Lived body and the Other's gaze: a phenomenological perspective on feeding and eating disorders

According to the phenomenological perspective, the lived body disorder is a core feature of feeding and eating disorders (FEDs). Persons with FEDs experience their own body first of all as an object looked by another person, rather than coenaesthetically or from a first-person perspective. In particular, the main features of this disorder are: alienation from the own body and from the own emotions, disgust for it, shame, and an exaggerated preoccupation for the way in which one appears to the others. Phenomenological research has recently highlighted that the gaze of the Other plays an important role. Because persons with FEDs cannot have an experience of their own body from within or coenesthetically, they need to apprehend their own body from outside through the gaze of the Other. This way of apprehending one's own body when it is looked by another person is called by Sartre the 'lived body-for-others'. Normally, the constitution of one's own body, and consequently of one's own Self and identity depends on the dialectic integration between the first-person apprehension of one's body (lived body) that it is based on coenaesthesia, and the third-person one, that it is based on the sense of sight (lived-body-for-others). When the dialectic is unbalanced toward the pole of the lived-body-for-others, experienced from without, the symptom occurs. Starting from these clinical observations, the so-called Optical-Coenaesthetic Disproportion model has been developed. In this paper, we describe this model, its philosophical and clinical foundations, and finally its clinical implication and its relationship with other disciplines, i.e., neurosciences. Level of evidence: V.

Body size overestimation in anorexia nervosa: Contributions of cognitive, affective, tactile and visual information

Body image disturbance (BID) in anorexia nervosa (AN) is poorly understood and the individual contribution of perceptual, cognitive, and affective components remains unclear. This study compared females with AN and matched healthy controls (HC) on a perceptual size estimation task. Participants (AN n=19 M[SD] age=16.97[2.24], HC n=19, age=15.77[2.17]) were blindfolded and estimated the size of neutral objects, safe foods, unsafe foods, and parts of their bodies (hips, waist, knees, ankle) over three blocks using: 1) no sensory information (baseline), 2) tactile information, and 3) added visual information. There were no significant differences between AN and HC on neutral and safe or unsafe food objects. Participants with AN were significantly more likely to overestimate their body size across blocks compared to HC. Both groups made fewer errors on unsafe foods and body parts when using tactile or visual information compared to baseline. Exploratory analyses revealed significant correlations between body size overestimation and drive for thinness and body dissatisfaction in the AN group, with body dissatisfaction being the most robust. Results suggest that both deficits in tactile and visual perception and affective factors play a role in BID for young women with AN.

Executive functioning and spatial processing in anorexia nervosa: an experimental study and its significance for the allocentric lock theory

PURPOSE

The allocentric lock theory (ALT) suggests that people with eating disorders have difficulties in multisensory integration in two reference frames-egocentric and allocentric, whereby the egocentric, but not allocentric, is impaired. This leads to a distorted body image that contributes to the development and maintenance of the disorder. The current study aimed to explore a facet of the ALT, namely, the visuo-spatial aspect, and its relation to cognitive flexibility in patients with anorexia nervosa (AN).

METHODS

Fifty-five participants took part in the study: 20 AN patients and 35 controls, matched by age and education. The object perspective taking test (OPTT) and the mental rotation test (MRT), tapping egocentric and allocentric representations, respectively, and a set-shifting task were administered. The brief symptom inventory was used to measure overall levels of distress.

RESULTS

AN patients showed higher level of distress. They performed poorer on the OPTT and set-shifting task but not on the MRT. The OPTT and MRT were correlated for controls but not for AN patients, while the set-shifting task and body mass index were associated with the OPTT but not with the MRT for the AN patients.

CONCLUSIONS

The findings support the ALT by demonstrating impaired visual egocentric representations and intact allocentric visual functions in AN patients, with cognitive flexibility associated only with the egocentric frame. Therefore, egocentric frame impairment in AN patients may be influenced by visual perception and cognitive flexibility deficiency.

LEVEL OF EVIDENCE

Level III: case-control analytic study.

The Pathogenic and Therapeutic Potential of the Gaze of the Other in the Clinic of "Eating Disorders"

Building on the optical-coenaesthetic disproportion model of so-called eating disorders, this paper provides a framework for the psychotherapy of people affected by these conditions. This model characterizes "eating disorders" as disorders of embodiment and identity, where a sense of unfamiliarity with one's own flesh, experienced as shifting and incomprehensible, leads to an impairment in the constitution of the Self and thus of one's own identity. Since there is a deficit of the coenaesthetic experience of the embodied Self, greater importance is assumed by body perception conveyed from without. To these persons, their corporeality is principally given as a body-object "to be seen" from a third-person perspective, rather than as a body-subject "to be felt" from a first-person perspective. The Other's look serves as an optical prosthesis to cope with dis-coenaesthesia and as a device through which these persons can define themselves. They are unable to accept the hiatus between "being a body" and "having a body," constitutively present in every human being, forcibly trying to recouple it, and finally ending up objectifying themselves to succeed. The external foundation of the Self thus takes the form of a constriction one can never be completely free of. Psychotherapy should thus accompany persons affected by eating disorders in their encounter with the miscarried dialectic between feeling oneself from within and seeing oneself from without through the gaze of the Other, so keenly feared by people desperately in search of self-control. Tactfully, the clinician accompanies the patient in taking a stance towards her symptom as the outcome of this miscarried dialectics, which is one premise for overcoming it. The clinician's gaze becomes the herald of recognition, allowing the patient to feel accepted in terms of her individuality. Feeling themselves touched by a gaze that waives its alienating potential in order to signify acceptance reactivates the identity-forming dialectics. Their body is thus revealed as the receiver of gazes, but also rediscovers its own possibility for self-determination starting out from these gazes. This intersubjective resonance between the clinician's gaze and the patient reactivates the identity-making dialectics between body-subject and body-object, creating the relational premises for overcoming the symptom.

Assessing the Relationship Between Attitudinal and Perceptual Component of Body Image Disturbance Using Virtual Reality

Body image disturbance (BID) affects quality of life even in the absence of clinically diagnosable eating pathology, and numerous studies have shown its crucial role in the emergence and maintenance of eating disorders. This study aimed at exploring attitudinal and perceptual components of BID using a novel virtual reality (VR)-based paradigm. A community sample of women (N = 27) recreated in VR their perceived body in both an allocentric (third-person view) and egocentric (first-person view) perspective. Specifically, women were able to choose between a wide range of three-dimensional bodies spanning body mass index 12.5-42.5 kg/m². Attitudinal indexes of BID (body dissatisfaction, body uneasiness, and body image avoidance) were assessed through questionnaires. Attitudinal components predicted the perceptual BID only in the allocentric perspective. Specifically, overestimation was predicted by body image avoidance, while underestimation was predicted by body uneasiness. Furthermore, a common predictor of underestimation and overestimation was body dissatisfaction. In line with the allocentric lock hypothesis, the current results seem to confirm the presence of two different mechanisms underlying BID: one related to real-time perception-driven inputs (egocentric frame) and one related to abstract knowledge, beliefs, and attitudes related to a person's body (allocentric frame). These findings contribute to a better understanding of the nature and mechanisms underlying BID and provide additional evidence about the suitability of using VR for exploring and assessing body image-related components and disturbances.

The Optical-Coenaesthetic Disproportion Hypothesis of Feeding and Eating Disorders in the Light of Neuroscience

This article builds on and extends the 'optical-coenaesthetic disproportion' (OCDisp) hypothesis of feeding and eating disorders (FEDs) matching data obtained through clinical research with laboratory evidence from neuroscience and neuropsychological studies. The OCDisp hypothesis, developed through the assessment in clinical setting of bodily experience using the IDentity and EAting (IDEA) disorder questionnaire, argues that in persons with FED the internal perception of one's embodied self (i.e., coenaesthesia) is deeply affected (their possibility to feel themselves is weakened or threatened by coenaesthopathic and emotional paroxysms; their bodily feelings are discontinuous over time), and as a compensation to it, these persons experience their own body as an object that is looked at by others. To FED persons, their body is principally given to them as an object 'to be seen.' The other's look serves as an optical prosthesis to cope with hypo- and dis-coenaesthesia and as a device through which persons with FED can define themselves and attenuate the anxiety produced by the conflicts between being-oneself and being-for-others. After describing the OCDisp hypothesis, we will gather evidence supporting it with neuroscience studies on FED. Our focus will be on data pointing to dampened multisensory integration of interoceptive and esteroceptive signals, demonstrating a predominance of the visual afferents toward signals arising within the body. In the final part of the article, we will show consistencies but also draw distinctions between our clinical hypothesis and neuroscience-based data and hypotheses and draft a potential agenda for translational research inspired by these.

Locked to a wrong body: Eating disorders as the outcome of a primary disturbance in multisensory body integration

In his recent paper "Distorted body representations in anorexia nervosa" Gadsby (2017) discussed empirical evidence regarding anorexic patients' distorted body representations. In particular, he interpreted them using the O'Shaughnessy's long-term body image (LTB) hypothesis (O'Shaughnessy, 1998): individuals with anorexia nervosa (AN) have a distorted LTB that tracks changes in the spatial content of the body and supplies this distorted content to other body representations. Even if we agree on the involvement of body memory in the distorted body representation, an open issue not fully addressed in the paper is: why AN patients do not update their LTBs to reflect their true dimensions? Our correspondence tries to answer to this question using a new neuropsychological and neurobiological theory: the Allocentric Lock Theory - ALT.

The neuroscience of body memory: From the self through the space to the others

Our experience of the body is not direct; rather, it is mediated by perceptual information, influenced by internal information, and recalibrated through stored implicit and explicit body representation (body memory). This paper presents an overview of the current investigations related to body memory by bringing together recent studies from neuropsychology, neuroscience, and evolutionary and cognitive psychology. To do so, in the paper, I explore the origin of representations of human body to elucidate their developmental process and, in particular, their relationship with more explicit concepts of self. First, it is suggested that our bodily experience is constructed from early development through the continuous integration of sensory and cultural data from six different representations of the body, i.e., the Sentient Body (Minimal Selfhood), the Spatial Body (Self Location), the Active Body (Agency), the Personal Body (Whole Body Ownership - Me); the Objectified Body (Objectified Self - Mine), and the Social Body (Body Satisfaction - Ideal Me). Then, it is suggested that these six representations can be combined in a coherent supramodal representation, i.e. the "body matrix", through a predictive, multisensory processing activated by central, top-down, attentional processes. From an evolutionary perspective, the main goal of the body matrix is to allow the self to protect and extend its boundaries at both the homeostatic and psychological levels. From one perspective, the self extends its boundaries (peripersonal space) through the enactment and recognition of motor schemas. From another perspective, the body matrix, by defining the boundaries of the body, also defines where the self is present, i.e., in the body that is processed by the body matrix as the most likely to be its one, and in the space surrounding it. In the paper I also introduce and discuss the concept of "embodied medicine": the use of advanced technology for altering the body matrix with the goal of improving our health and well-being.

Evidence for alterations of cortical folding in anorexia nervosa

Anorexia nervosa (AN) is highly heritable, and the perspective on the etiology of AN has changed from a behavioral to a neurobiological and neurodevelopmental view. However, cortical folding as an important marker for deviations in brain development has yet rarely been explored in AN. Hence, in order to determine potential cortical folding alterations, we investigated fine-grained cortical folding in a cohort of 26 patients with AN, of whom 6 patients were recovered regarding their weight at the time point of MRI measurement. MRI-derived cortical folding was computed and compared between patients and healthy controls at about 150,000 points per hemisphere using a surface-based technique (FreeSurfer). Patients with AN exhibited highly significant increased cortical folding in a right dorsolateral prefrontal cortex region (DLPFC). Furthermore, a statistical trend in the same direction was found in the right visual cortex. We did not find a correlation of local cortical folding and current symptoms of the disease. In conclusion, our analyses provide first evidence that altered DLPFC cortical folding plays a role in the etiology of AN. The absence of correlations with clinical parameters implicates a relatively independence of cortical folding alterations from the current symptomatology and might thus be regarded as a trait characteristic of the disease potentially related to other neurobiological features of AN.

Altered exposure-related reshaping of body appreciation in adolescent patients with anorexia nervosa

Several studies suggest a relation between repeated exposure to extremely thin bodies in media and the perceptual and emotional disturbances of body representation in anorexia nervosa (AN). In this study, we utilized an exposure paradigm to investigate how perceptual experience modulates body appreciation in adolescents with AN as compared to healthy adolescents. Twenty AN patients and 20 healthy controls were exposed to pictures of thin or round models and were then required to express liking judgments about bodies of variable weight. Brief exposure to round models increased the liking judgments of round bodies but not those of thin bodies in healthy adolescents. Furthermore, exposure to round models increased the liking judgments of both thin and round bodies in adolescents with AN. Patients did not show any change of liking judgments after exposure to thin models. These results point to weak norm-based reshaping of body appreciation in AN patients.

Neurobiology of Anorexia Nervosa: Serotonin Dysfunctions Link Self-Starvation with Body Image Disturbances through an Impaired Body Memory

The etiology of anorexia nervosa (AN) is still unclear, despite that it is a critical and potentially mortal illness. A recent neurobiological model considers AN as the outcome of dysfunctions in the neuronal processes related to appetite and emotionality (Kaye et al., 2009, 2013). However, this model still is not able to answer a critical question: What is behind body image disturbances (BIDs) in AN? The article starts its analysis from reviewing some of the studies exploring the effects of the serotonin systems in memory (episodic, working, and spatial) and its dysfunctions. The review suggests that serotonin disturbances may: (a) facilitate the encoding of third person (allocentric) episodic memories; (b) facilitate the consolidation of emotional episodic memories (e.g., teasing), if preceded by repeated stress; (c) reduce voluntary inhibition of mnestic contents; (d) impair allocentric spatial memory. If we discuss these results within the interpretative frame suggested by the “Allocentric Lock Hypothesis” (Riva, 2012, 2014), we can hypothesize that altered serotoninergic activity in AN patients: (i) improves their ability to store and consolidate negative autobiographical memories, including those of their body, in allocentric perspective; (ii) impairs their ability to trigger voluntary inhibition of the previously stored negative memory of the body; (iii) impairs their capacity to retrieve/update allocentric information. Taken together, these points suggest a possible link between serotonin dysfunctions, memory impairments and BIDs: the impossibility of updating a disturbed body memory using real time experiential data—I'm locked to a wrong body stored in long term memory—pushes AN patients to control body weight and shape even when underweight.

Virtual Reality in the Assessment and Treatment of Weight-Related Disorders

Virtual Reality (VR) has, for the past two decades, proven to be a useful adjunctive tool for both assessment and treatment of patients with eating disorders and obesity. VR allows an individual to enter scenarios that simulate real-life situations and to encounter food cues known to trigger his/her disordered eating behavior. As well, VR enables three-dimensional figures of the patient's body to be presented, helping him/her to reach an awareness of body image distortion and then providing the opportunity to confront and correct distortions, resulting in a more realistic body image and a decrease in body image dissatisfaction. In this paper, we describe seminal studies in this research area.

Future Directions: How Virtual Reality Can Further Improve the Assessment and Treatment of Eating Disorders and Obesity

Transdisciplinary efforts for further elucidating the etiology of eating and weight disorders and improving the effectiveness of the available evidence-based interventions are imperative at this time. Recent studies indicate that computer-generated graphic environments-virtual reality (VR)-can integrate and extend existing treatments for eating and weight disorders (EWDs). Future possibilities for VR to improve actual approaches include its use for altering in real time the experience of the body (embodiment) and as a cue exposure tool for reducing food craving.

Altered resting state functional connectivity of anterior cingulate cortex in drug naïve adolescents at the earliest stages of anorexia nervosa

Previous Resting-State Functional Connectivity (RSFC) studies have shown several functional alterations in adults with or recovered from long Anorexia Nervosa (AN). The aim of this paper was to investigate whole brain RSFC in adolescents with AN in the earliest stages, less than 6 months, of the disorder. Sixteen drug-naïve outpatient female adolescents with AN-restrictive type (AN-r) (mean age: 15,8; SD 1,7) were compared to 16 age-matched healthy female (mean age: 16,3; SD 1,4). Relevant resting state networks (RSNs) were identified using independent component analysis (ICA) from functional magnetic resonance imaging data; a dual regression technique was used to detect between-group differences in the RSNs. Between-group differences of the functional connectivity maps were found in the executive control network (ECN). Particularly, decreased temporal correlation was observed in AN-r patients relative to healthy controls between the ECN functional connectivity maps and the anterior cingulate cortex (p < 0.05 corrected). Our results in AN adolescents may represent an early trait-related biomarker of the disease. Considering that the above mentioned network and its area are mainly involved in cognitive control and emotional processing, our findings could explain the impaired cognitive flexibility in relation to body image and appetite in AN patients.

The Neuropsychology of Self-Objectification

According to the objectification theory ( Fredrickson & Roberts, 1997 ) girls and women are thought to adopt a self-objectified view of themselves as objects to be evaluated on the basis of their appearance. More, this experience is proposed to have a direct link with the health and well being of female subjects. The paper analyzes and discusses the objectification theory within the context of recent research on memory and spatial cognition. On one side, it describes self-objectification as a specific cognitive process: a woman internalizes an objectified self image, when she uses an allocentric frame of reference (observer mode) to remember events in which she evaluates herself based upon bodily appearance. On the other side it directly connects the objectification theory with the Allocentric Lock Hypothesis ( Riva, 2012 ), suggesting that eating disorders have as antecedent an allocentric (objective, from outside) negative image schema of the body that is no more updated by egocentric sensory inputs from perception. Both the similarities between the allocentric lock and the out-of-body experience and a review of the recent studies supporting this claim are also presented and discussed.

Nonvisual multisensory impairment of body perception in anorexia nervosa: a systematic review of neuropsychological studies

Background

Body image distortion is a central symptom of Anorexia Nervosa (AN). Even if corporeal awareness is multisensory majority of AN studies mainly investigated visual misperception. We systematically reviewed AN studies that have investigated different nonvisual sensory inputs using an integrative multisensory approach to body perception. We also discussed the findings in the light of AN neuroimaging evidence.

Methods

PubMed and PsycINFO were searched until March, 2014. To be included in the review, studies were mainly required to: investigate a sample of patients with current or past AN and a control group and use tasks that directly elicited one or more nonvisual sensory domains.

Results

Thirteen studies were included. They studied a total of 223 people with current or past AN and 273 control subjects. Overall, results show impairment in tactile and proprioceptive domains of body perception in AN patients. Interoception and multisensory integration have been poorly explored directly in AN patients. A limitation of this review is the relatively small amount of literature available.

Conclusions

Our results showed that AN patients had a multisensory impairment of body perception that goes beyond visual misperception and involves tactile and proprioceptive sensory components. Furthermore, impairment of tactile and proprioceptive components may be associated with parietal cortex alterations in AN patients. Interoception and multisensory integration have been weakly explored directly. Further research, using multisensory approaches as well as neuroimaging techniques, is needed to better define the complexity of body image distortion in AN.

Key Findings

The review suggests an altered capacity of AN patients in processing and integration of bodily signals: body parts are experienced as dissociated from their holistic and perceptive dimensions. Specifically, it is likely that not only perception but memory, and in particular sensorimotor/proprioceptive memory, probably shapes bodily experience in patients with AN.

Out of my real body: cognitive neuroscience meets eating disorders

Clinical psychology is starting to explain eating disorders (ED) as the outcome of the interaction among cognitive, socio-emotional and interpersonal elements. In particular two influential models—the revised cognitive-interpersonal maintenance model and the transdiagnostic cognitive behavioral theory—identified possible key predisposing and maintaining factors. These models, even if very influential and able to provide clear suggestions for therapy, still are not able to provide answers to several critical questions: why do not all the individuals with obsessive compulsive features, anxious avoidance or with a dysfunctional scheme for self-evaluation develop an ED? What is the role of the body experience in the etiology of these disorders? In this paper we suggest that the path to a meaningful answer requires the integration of these models with the recent outcomes of cognitive neuroscience. First, our bodily representations are not just a way to map an external space but the main tool we use to generate meaning, organize our experience, and shape our social identity. In particular, we will argue that our bodily experience evolves over time by integrating six different representations of the body characterized by specific pathologies—body schema (phantom limb), spatial body (unilateral hemi-neglect), active body (alien hand syndrome), personal body (autoscopic phenomena), objectified body (xenomelia) and body image (body dysmorphia). Second, these representations include either schematic (allocentric) or perceptual (egocentric) contents that interact within the working memory of the individual through the alignment between the retrieved contents from long-term memory and the ongoing egocentric contents from perception. In this view EDs may be the outcome of an impairment in the ability of updating a negative body representation stored in autobiographical memory (allocentric) with real-time sensorimotor and proprioceptive data (egocentric).

Virtual reality for enhancing the cognitive behavioral treatment of obesity with binge eating disorder: randomized controlled study with one-year follow-up

BACKGROUND

Recent research identifies unhealthful weight-control behaviors (fasting, vomiting, or laxative abuse) induced by a negative experience of the body, as the common antecedents of both obesity and eating disorders. In particular, according to the allocentric lock hypothesis, individuals with obesity may be locked to an allocentric (observer view) negative memory of the body that is no longer updated by contrasting egocentric representations driven by perception. In other words, these patients may be locked to an allocentric negative representation of their body that their sensory inputs are no longer able to update even after a demanding diet and a significant weight loss.

OBJECTIVE

To test the brief and long-term clinical efficacy of an enhanced cognitive-behavioral therapy including a virtual reality protocol aimed at unlocking the negative memory of the body (ECT) in morbidly obese patients with binge eating disorders (BED) compared with standard cognitive behavior therapy (CBT) and an inpatient multimodal treatment (IP) on weight loss, weight loss maintenance, BED remission, and body satisfaction improvement, including psychonutritional groups, a low-calorie diet (1200 kcal/day), and physical training.

METHODS

90 obese (BMI>40) female patients with BED upon referral to an obesity rehabilitation center were randomly assigned to conditions (31 to ECT, 30 to CBT, and 29 to IP). Before treatment completion, 24 patients discharged themselves from hospital (4 in ECT, 10 in CBT, and 10 in IP). The remaining 66 inpatients received either 15 sessions of ECT, 15 sessions of CBT, or no additional treatment over a 5-week usual care inpatient regimen (IP). ECT and CBT treatments were administered by 3 licensed psychotherapists, and patients were blinded to conditions. At start, upon completion of the inpatient treatment, and at 1-year follow-up, patients' weight, number of binge eating episodes during the previous month, and body satisfaction were assessed by self-report questionnaires and compared across conditions. 22 patients who received all sessions did not provide follow-up data (9 in ECT, 6 in CBT, and 7 in IP).

RESULTS

Only ECT was effective at improving weight loss at 1-year follow-up. Conversely, control participants regained on average most of the weight they had lost during the inpatient program. Binge eating episodes decreased to zero during the inpatient program but were reported again in all the three groups at 1-year follow-up. However, a substantial regain was observed only in the group who received the inpatient program alone, while both ECT and CBT were successful in maintaining a low rate of monthly binge eating episodes.

CONCLUSIONS

Despite study limitations, findings support the hypothesis that the integration of a VR-based treatment, aimed at both unlocking the negative memory of the body and at modifying its behavioral and emotional correlates, may improve the long-term outcome of a treatment for obese BED patients. As expected, the VR-based treatment, in comparison with the standard CBT approach, was able to better prevent weight regain but not to better manage binge eating episodes.