Neural correlates of body dissatisfaction in anorexia nervosa
Introduction
Body dissatisfaction is important in the development, maintenance and relapse of eating disorders (ED) including anorexia nervosa (AN) (Jacobi et al., 2004, Stice and Shaw, 2002, Taylor et al., 2006, Windauer et al., 1993). Furthermore, “undue influence of weight and shape on self evaluation” is a diagnostic feature of AN (American Psychiatric Association, 1994). The body dissatisfaction present in people with AN is associated with a perceptual disturbance, an overestimation of body size (Cash & Deagle, 1997).
Exposure to media images of female bodies and self-other comparison of body-shape elicits dissatisfaction with one's own body and emotional distress (i.e. anxiety) (Groesz, Levine, & Murnen, 2002). AN patients (despite their low body weight) report higher levels of anxiety when confronted with slim fashion models (Friederich et al., 2006) or line drawings of slim bodies (Uher et al., 2005).
One mechanism that may contribute to heightened body dissatisfaction in people with AN is an overestimation of their body size (Cash & Deagle, 1997). As this problem is restricted to the estimation of their own body, there is an apparent inaccuracy in self-body representation and awareness and this is supported by recent data showing that they have an impaired perception of physiological feedback from their own body (Papezova et al., 2005, Pollatos et al., 2008, Wagner et al., 2008).
Functional neuroimaging studies have identified a neural network responsible for processing body-shape related information, comprised of the lateral occipitotemporal gyrus (including the extrastriate body area (EBA) and the fusiform body area (FBA)), the dorsolateral prefrontal cortex (PFC) and the parietal lobe, particularly within the right hemisphere (Friederich et al., 2007, Uher et al., 2005, Wagner et al., 2003). Within this network, the occipito-parietal pathway is primarily involved in the detection of body related information and the parieto-frontal pathway represents body identification and self-other discrimination (Hodzic et al., 2009a, Hodzic et al., 2009b).
Brain activations within the limbic network have been found in healthy controls exposed to distorted self-images (Kurosaki et al., 2006, Miyake et al., 2010, Wagner et al., 2003), to self-other comparison of body shape (Friederich et al., 2007) and by using derogatory body-shape-related words (Shirao, Okamoto, Okada, Okamoto, & Yamawaki, 2003). These studies suggest an engagement of the limbic network including the prefrontal cortex, striatum and temporomesial structures including the amygdala that becomes activated in these conditions.
Functional imaging studies in healthy individuals have identified the sensorimotor cortex including the mid-dorsal insula, the anterior insula and the anterior cingulate cortex as neural correlates for the representation of physiological feedback from the body and all subjective feelings from the body (Craig, 2003, Pollatos et al., 2007).
In patients with AN, several neuroimaging studies have investigated body image disturbance in response to body-shape images using whole brain analyses. In these, group differences with healthy controls were found primarily in the body-shape processing network (Beato-Fernandez et al., 2009, Uher et al., 2005, Wagner et al., 2003). Additionally, during visual self-recognition (processing of self-images compared to non-self-images) and during exposure to distorted thin self-images, patients with AN showed altered insula activation (Mohr et al., in press, Sachdev et al., 2008).
One study specifically assessed brain activation in the ventral striatal system and reported greater ventral striatal activity to underweight compared to normal weight body images in AN patients, whereas healthy controls showed a reversed pattern (Fladung et al., 2010). The authors suggest that increased metabolism in the reward system to underweight body images (i.e. starvation associated cues) support theories of starvation dependence in AN patients. However, it remains unclear whether body dissatisfaction in AN is associated with alterations in the ventral limbic network and/or in self-body representation and interoception.
In the present study, we have enhanced the stimuli and the presentation protocol, on the basis of our previous experience with a body image paradigm (Uher et al., 2005) and induced self-schematic processing by giving instructions that encouraged participants to evaluate their own physical appearance in comparison to thin ideals. In contrast to paradigms of self-body recognition and self-body identification from externally presented self-images, the aim of the present paradigm was to induce interoceptive and emotional–motivational processing triggered by a self-other body-shape comparison. Using this paradigm we previously found that in healthy women, activations of the limbic system were associated with anxiety (Friederich et al., 2007).
As patients with AN show higher anxiety in response to media images (Friederich et al., 2007), we hypothesized that (i) body-shape comparison is associated with greater activation of the ventral limbic system (i.e. ventral striatum, mesial temporal regions including the amygdala, rostral anterior cingulate cortex (ACC), ventral PFC) (Phillips, Drevets, Rauch, & Lane, 2003). Given the apparent inaccuracy in the estimation of one's own body size, we also hypothesized that (ii) areas involved in the processing of interoceptive awareness and self-body representation such as the insular cortex, sensorimotor cortical regions and the ACC would be differentially engaged in the patient compared to the control group (Craig, 2003, Critchley et al., 2004).
Section snippets
Participants
Thirty-five right handed women aged between 18 and 35 years were enrolled in the study, 17 patients with a DSM diagnosis of AN and 18 age-matched healthy females in the normal weight range and without a lifetime diagnosis of a psychiatric disease. The patients with AN were recruited from the South London and Maudsley NHS Trust. This is a newly recruited group of patients and there is no overlap with groups of patients reported previously (Uher et al., 2005). The HC group was recruited by
Results
There were no group differences on demographic variables. As expected, patients with AN had higher scores on eating and shape related attitudes compared to the HC group. Approximately half of the patients were on antidepressant medication of the SSRI type. Of the 17 patients with AN, 10 were restrictors and 7 were of the binge-purge subtype (Table 1). Patients with purging AN had higher scores on the restrained eating and shape concern subscales of the EDEQ, but were comparable to restrictors
Discussion
Using fMRI, we have identified differences in neural correlates of self-other comparison of body shape between AN patients and controls.
AN patients in comparison to controls showed higher body dissatisfaction and greater emotional distress (i.e. anxiety) to self-other body-comparison. However in contrast to HC, AN patients showed no close association between anxiety ratings to body-comparison and body dissatisfaction ratings. Due to this finding we have differentiated between body
Acknowledgments
This study was supported by the Nina Jackson Eating Disorders Research Charity and a Christina-Barz Travelling Fellowship for H.-C. Friederich. We thank the magazine “Freundin” for generously providing the picture material.
References (47)
- et al.
Changes in regional cerebral blood flow after body image exposure in eating disorders
Psychiatry Research
(2009) - et al.
Conflict monitoring and anterior cingulate cortex: An update
Trends in Cognitive Sciences
(2004) - et al.
Generic brain activation mapping in functional magnetic resonance imaging: A nonparametric approach
Magnetic Resonance Imaging
(1997) - et al.
Cognitive and emotional influences in anterior cingulate cortex
Trends in Cognitive Sciences
(2000) - et al.
I’m not as slim as that girl: Neural bases of body shape self-comparison to media images
Neuroimage
(2007) - et al.
Distinct cortical networks for the detection and identification of human body
Neuroimage
(2009) - et al.
Neural predictors of purchases
Neuron
(2007) - et al.
Distorted images of one's own body activates the prefrontal cortex and limbic/paralimbic system in young women: A functional magnetic resonance imaging study
Biological Psychiatry
(2006) - et al.
Brain activation during the perception of distorted body images in eating disorders
Psychiatry Research
(2010) - et al.
Elevated pain threshold in eating disorders: Physiological and psychological factors
Journal of Psychiatric Research
(2005)
An insular view of anxiety
Biological Psychiatry
Functional neuroanatomy of emotion: A meta-analysis of emotion activation studies in PET and fMRI
Neuroimage
Neurobiology of emotion perception I: The neural basis of normal emotion perception
Biological Psychiatry
Action monitoring and perfectionism in anorexia nervosa
Brain and Cognition
Reduced perception of bodily signals in anorexia nervosa
Eating Behaviours
Brains of anorexia nervosa patients process self-images differently from non-self-images: An fMRI study
Neuropsychologia
Role of body dissatisfaction in the onset and maintenance of eating pathology: A synthesis of research findings
Journal of Psychosomatic Research
Analysis of a large fMRI cohort: Statistical and methodological issues for group analyses
Neuroimage
Recovery and chronicity in anorexia nervosa: Brain activity associated with differential outcomes
Biological Psychiatry
Functional neuroanatomy of body shape perception in healthy and eating-disordered women
Biological Psychiatry
Diagnostic and statistical manual of mental disorders (DSM IV)
Attitudinal body-image assessment: Factor analysis of the Body-Self Relations Questionnaire
Journal of Personality Assessment
Global, voxel, and cluster tests, by theory and permutation, for a difference between two groups of structural MR images of the brain
IEEE Transactions on Medical Imaging
Cited by (113)
Neural mechanisms of perceptual and affective body-image disturbance during own-body and ideal-body estimation
2023, Behavioural Brain ResearchThe neural correlates of socio-cognitive factors and eating disorders in young people: A systematic review
2022, Journal of Psychiatric ResearchThe cerebellum gains weight: A systematic review of alterations in cerebellar volume and cerebro-cerebellar functional alterations in individuals with eating disorders
2022, Neuroscience and Biobehavioral ReviewsCitation Excerpt :Along with information on brain volumetric changes, chief information on brain modifications in individuals with EDs has been conveyed by the use of in vivo MRI techniques examining brain functionality. Current theories in the pathophysiology of EDs emerging from MRI studies mostly focus on cortical-striatal-limbic circuits that sustain reward processing and habit formation (Friederich et al., 2010, 2012; Smith and Robbins, 2013; O’Hara et al., 2015; Steward et al., 2018), orbital-frontal and prefrontal networks with respect to cognitive and executive control (Treasure et al., 2012; Berner and Marsh, 2014; Geisler et al., 2017; Kullmann et al., 2014; Steward et al., 2018), self-monitoring networks consisting of the fusiform gyrus, the precuneus, and the prefrontal cortex that are involved in body-image perception (Mohr et al., 2011; Esposito et al., 2016; Steward et al., 2018) and affective-related circuits comprising the amygdala, the insula and regions in the prefrontal cortex (Davis and Woodside, 2002; Kaye et al., 2009; Botvinick, 2007; Bischoff-Grethe et al., 2013; Steward et al., 2018). Bottom-up (BU) and top-down (TD) models have been proposed for EDs functions related to restrictive eating habits (Steward et al., 2018).
Striatal volumes as potential biomarkers in Eating Disorders: A pilot study
2022, Revista de Psiquiatria y Salud MentalEffectiveness of non-pharmacological interventions on individuals with anorexia nervosa: A systematic review and meta-analysis
2022, Patient Education and Counseling