Body image distortion reveals amygdala activation in patients with anorexia nervosa -- a functional magnetic resonance imaging study

The neural substrates responsible for punishment sensitivity association with procrastination: Left putamen connectivity with left middle temporal gyrus

Procrastination has adverse consequences across cultural contexts. Behavioral research found a positive correlation between punishment sensitivity and procrastination. However, little is known about the neural substrates underlying the association between them. We employed voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods to address this issue with two independent samples. In Sample 1, behavioral results found that punishment sensitivity was positively related to procrastination. The VBM analysis showed that punishment sensitivity was negatively correlated with gray matter volume in left putamen. Subsequently, the RSFC results revealed that left putamen - left middle temporal gyrus (MTG) connectivity was positively associated with punishment sensitivity. More crucially, mediation analysis indicated that left putamen - left MTG connectivity mediated the relationship between punishment sensitivity and procrastination. The aforementioned results were validated in Sample 2. Altogether, left putamen - left MTG connectivity might be the neural signature of the association between punishment sensitivity and procrastination.

Reduced body-image disturbance by body-image interventions is associated with neural-response changes in visual and social processing regions: a preliminary study

Introduction

Body-image disturbance is a major factor in the development of eating disorders, especially among young women. There are two main components: perceptual disturbance, characterized by a discrepancy between perceived and actual body size, and affective disturbance, characterized by a discrepancy between perceived and ideal body size. Interventions targeting body-image disturbance ask individuals to describe their own body without using negative expressions when either viewing it in a mirror or imagining it. Despite the importance of reducing body-image disturbance, its neural mechanisms remain unclear. Here we investigated the changes in neural responses before and after an intervention. We hypothesized that neural responses correlated with the degree of body-image disturbance would also be related to its reduction, i.e., a reduction in perceptual and affective disturbances would be related to changes in attentional and socio-cognitive processing, respectively.

Methods

Twenty-eight young adult women without known psychiatric disorders underwent a single 40-min intervention. Participants completed tasks before and after the intervention, in which they estimated their perceived and ideal body sizes using distorted silhouette images to measure body-image disturbance. We analyzed the behavioral and neural responses of participants during the tasks.

Results

The intervention did not significantly reduce body-image disturbance. Analysis of individual differences showed distinct changes in neural responses for each type of disturbance. A decrease in perceptual disturbance was associated with bodily visuospatial processing: increased activation in the left superior parietal lobule, bilateral occipital gyri, and right cuneus. Reduced affective disturbance was associated with socio-cognitive processing; decreased activation in the right temporoparietal junction, and increased functional connectivity between the left extrastriate body area and the right precuneus.

Discussion

We identified distinct neural mechanisms (bodily visuospatial and socio-cognitive processing) associated with the reduction in each component of body-image disturbance. Our results imply that different neural mechanisms are related to reduced perceptual disturbance and the expression thereof, whereas similar neural mechanisms are related to the reduction and expression of affective disturbance. Considering the small sample size of this study, our results should be regarded as preliminary.

Neural correlates of distorted body images in adolescent girls with anorexia nervosa: How is it different from major depressive disorder?

Body image disturbance is closely linked to eating disorders including anorexia nervosa (AN). Distorted body image perception, dissatisfaction and preoccupation with weight and shape are often key factors in the development and maintenance of these disorders. Although the pathophysiological mechanism of body image disorder is not yet fully understood, aberrant biological processes may interfere with perceptive, cognitive and emotional aspects of body image. This study focuses on the neurobiological aspects of body image disturbance. The sample consisted of 12 adolescent girls diagnosed with AN, nine girls with major depressive disorder (MDD) and 10 without psychiatric diagnoses (HC, the healthy control group). We applied a block-design task in functional magnetic resonance imaging using participants' original and distorted overweight and underweight images. After imaging, the participants scored the images for resemblance, satisfaction and anxiety levels. The findings of this study demonstrate that overweight images elicited dissatisfaction and increased occipitotemporal activations across all participants. However, no difference was found between the groups. Furthermore, the MDD and HC groups showed increased activations in the prefrontal cortex and insula in response to underweight images compared to their original counterparts, whereas the AN group exhibited increased activations in the parietal cortex, cingulate gyrus and parahippocampal cortex in response to the same stimuli.

Neural underpinnings of threat bias in relation to loss-of-control eating behaviors among adolescent girls with high weight

Introduction

Loss-of-control (LOC) eating, a key feature of binge-eating disorder, may relate attentional bias (AB) to highly salient interpersonal stimuli. The current pilot study used magnetoencephalography (MEG) to explore neural features of AB to socially threatening cues in adolescent girls with and without LOC-eating.

Methods

Girls (12-17 years old) with overweight or obesity (BMI >85th percentile) completed an AB measure on an affective dot-probe AB task during MEG and evoked neural responses to angry or happy (vs. neutral) face cues were captured. A laboratory test meal paradigm measured energy intake and macronutrient consumption patterns.

Results

Girls (N = 34; Mage = 15.5 ± 1.5 years; BMI-z = 1.7 ± 0.4) showed a blunted evoked response to the presentation of angry face compared with neutral face cues in the left dorsolateral prefrontal cortex, a neural region implicated in executive control and regulation processes, during attention deployment (p < 0.01). Compared with those without LOC-eating (N = 21), girls with LOC-eating (N = 13) demonstrated a stronger evoked response to angry faces in the visual cortex during attention deployment (p < 0.001). Visual and cognitive control ROIs had trends suggesting interaction with test meal intake patterns among girls with LOC-eating (ps = 0.01).

Discussion

These findings suggest that girls with overweight or obesity may fail to adaptively engage neural regions implicated in higher-order executive processes. This difficulty may relate to disinhibited eating patterns that could lead to excess weight gain.

Brain functional alterations in patients with anorexia nervosa: A meta-analysis of task-based functional MRI studies

The goal of this study was to discern the neural activation patterns associated with anorexia nervosa (AN) in response to tasks related to body-, food-, emotional-, cognitive-, and reward- processing. A meta-analysis was performed on task-based fMRI studies, revealing that patients with AN showed increased activity in the left superior temporal gyrus and bilaterally in the ACC during a reward-related task. During cognitive-related tasks, patients with AN also showed increased activity in the left superior parietal gyrus, right middle temporal gyrus, but decreased activity in the MCC. Additionally, patients with AN showed increased activity bilaterally in the cerebellum, MCC, and decreased activity bilaterally in the bilateral precuneus/PCC, right middle temporal gyrus, left ACC when they viewed food images. During emotion-related tasks, patients with AN showed increased activity in the left cerebellum, but decreased activity bilaterally in the striatum, right mPFC, and right superior parietal gyrus. Patients with AN also showed increased activity in the right striatum and decreased activity in the right inferior temporal gyrus and bilaterally in the mPFC during body-related tasks. The present meta-analysis provides a comprehensive overview of the patterns of brain activity evoked by task stimuli, thereby augmenting the current comprehension of the pathophysiology in AN.

Neural mechanisms of perceptual and affective body-image disturbance during own-body and ideal-body estimation

Body-image disturbance is a core feature of eating disorders and can predict their development in healthy individuals. There are two components of body-image disturbance: perceptual disturbance (associated with overestimation of body size) and affective disturbance (associated with body dissatisfaction). Previous behavioral studies have hypothesized that attention to particular body parts and negative body-related emotions resulting from social pressure are associated with the respective degrees of perceptual and affective disturbance; however, the neural representations that underlie this hypothesis have not been elucidated. Thus, this study investigated the brain regions and connectivity associated with the degree of body-image disturbance. Specifically, we examined the brain activations associated with participants' estimation of the width of their actual and ideal bodies; we sought to determine which brain regions and functional connectivity from body-related visual processing regions were correlated with the degree of each component of body-image disturbance. The degree of perceptual disturbance was positively correlated with excessive width-dependent brain activations in the left anterior cingulate cortex when estimating one's body size; it was positively correlated with the functional connectivity between the left extrastriate body area and left anterior insula. The degree of affective disturbance was positively correlated with excessive width-dependent brain activation in the right temporoparietal junction and negatively correlated with functional connectivity between the left extrastriate body area and right precuneus when estimating one's ideal body size. These results support the hypothesis that perceptual disturbance is associated with attentional processing, whereas affective disturbance is associated with social processing.

Novel ketamine and zinc treatment for anorexia nervosa and the potential beneficial interactions with the gut microbiome

Anorexia nervosa (AN) is a severe illness with diverse aetiological and maintaining contributors including neurobiological, metabolic, psychological, and social determining factors. In addition to nutritional recovery, multiple psychological and pharmacological therapies and brain-based stimulations have been explored; however, existing treatments have limited efficacy. This paper outlines a neurobiological model of glutamatergic and γ-aminobutyric acid (GABA)-ergic dysfunction, exacerbated by chronic gut microbiome dysbiosis and zinc depletion at a brain and gut level. The gut microbiome is established early in development, and early exposure to stress and adversity contribute to gut microbial disturbance in AN, early dysregulation to glutamatergic and GABAergic networks, interoceptive impairment, and inhibited caloric harvest from food (e.g., zinc malabsorption, competition for zinc ions between gut bacteria and host). Zinc is a key part of glutamatergic and GABAergic networks, and also affects leptin and gut microbial function; systems dysregulated in AN. Low doses of ketamine in conjunction with zinc, could provide an efficacious combination to act on NMDA receptors and normalise glutamatergic, GABAergic and gut function in AN.

Anorexia nervosa as a disorder of the subcortical-cortical interoceptive-self

PURPOSE

Anorexia nervosa (AN) is characterized by a diminished capacity in perceiving the physiological correlates of interoceptive sensations, namely bodily self-consciousness. Given the neural division of self-processing into interoceptive-, exteroceptive- and mental-self, we hypothesize neural deficits in the interoceptive-processing regions in AN.

METHODS

To prove this, we reviewed resting state (rs), task and rest-task studies in AN literature.

RESULTS

Neuronal data demonstrate the following in AN: (i) decreased rs-functional connectivity (rsFC) of subcortical-cortical midline structures (SCMS); (ii) reduced rsFC between medial (default-mode network/DMN and salience network/SN) and lateral (executive-control network/ECN) cortical regions; (iii) decreased rsFC in mainly the regions of the interoceptive-self; (iv) altered activity with overall increased activity in response to sensory/body image stimuli, especially in the regions of the interoceptive-self; (v) lack of a clear task-related distinction between own's and others' body image.

CONCLUSION

These data may indicate that rs-hypoconnectivity between SCMS, as neural correlate of a reduced intero-exteroceptive integration resulting in self-objectification, might be linked to overall increased activity in interoceptive regions during sensory/body image stimuli in AN, engendering an "anxious bodily self."

LEVEL OF EVIDENCE

I: Systematic review.

Hypercholesterolemia in Cancer and in Anorexia Nervosa: A Hypothesis for a Crosstalk

The relationship between cholesterol and cancer has been widely demonstrated. Clinical studies have shown changes in blood cholesterol levels in cancer patients. In parallel, basic research studies have shown that cholesterol is involved in the mechanisms of onset and progression of the disease. On the other hand, anorexic patients have high cholesterol levels and a high susceptibility to cancer. In this review, we first present a brief background on the relations among nutrition, eating disorders and cancer. Using several notable examples, we then illustrate the changes in cholesterol in cancer and in anorexia nervosa, providing evidence for their important relationship. Finally, we show a new possible link between cholesterol disorder in cancer and in anorexia nervosa.

Higher general executive functions predicts lower body mass index by mitigating avoidance behaviors

BACKGROUND

The present study examines the relationship between obesity, executive functions, and body image in a nonclinical population from southern Italy.

METHODS

General executive functioning (Frontal Assessment Battery-15), and body image disturbances (Body Uneasiness Test) were assessed in a sample including 255 participants (138 females, M age = 43.51 years, SD = 17.94, range = 18-86 years; M body mass index (BMI) = 26.21, SD = 4.32, range = 18.03-38.79).

FINDINGS

Multiple Linear Regression Analysis indicated that age, years of education, FAB15 score, body image concerns, and avoidance predicted the variance of BMI. A subsequent mediation analysis highlighted that the indirect effect of FAB15 on BMI through avoidance was statistically significant.

INTERPRETATION

Our results suggest that more performing executive functioning predicts a decrease in BMI that is partially due to the mitigation of avoidance behaviors.

The costs of over-control in anorexia nervosa: evidence from fMRI and ecological momentary assessment

A growing body of evidence suggests that a high level of self-control may, despite its positive effects, influence cognitive processing in an unfavorable manner. However, the affective costs of self-control have only rarely been investigated. Anorexia nervosa (AN) is an eating disorder that is often characterized by excessive self-control. Here, we used fMRI to explore whether over-control in AN may have negative affective consequences. 36 predominantly adolescent female AN patients and 36 age-matched healthy controls (HC) viewed negative and neutral pictures during two separate fMRI sessions before and after 10 min of rest. We tested whether abnormally elevated neural activity during the initial presentation in a brain region broadly implicated in top-down control, the dorsolateral prefrontal cortex (dlPFC), could predict subsequent activation in limbic areas relevant to bottom-up affective processing. Using ecological momentary assessment (EMA), we also tested for associations between the aforementioned neuroimaging markers and negative affective states in the two weeks following the experiment. fMRI data revealed that higher initial activation of the dlPFC in AN predicted increased amygdala reactivity during the second fMRI session, which in turn was related to increased self-reported tension during two weeks following the scan. These data suggest that over-control in AN patients may come at a cost including negative affective states on a short (minutes) as well as a longer time scale (days). This mechanism may significantly contribute to the persistence of AN.

Body perception treatment, a possible way to treat body image disturbance in eating disorders: a case-control efficacy study

BACKGROUND

The body image disturbance (BID) is a common symptom in eating disorders, often observed and described in anorexia nervosa (AN) and bulimia nervosa (BN). Recently, this symptom has also been observed in binge eating disorder (BED). The research underlines that the BID presents three different altered components: affective, cognitive, and perceptual one. Current treatments for BID have mainly focused on the affective and cognitive components. Nowadays, the need emerges for treatments focused also on the perceptual component of the BID. In this paper, we present the results of an efficacy study on the body perception treatment (BPT), a new treatment for BID focused on the perceptual component of the disorder.

OBJECTIVE

We looked for an additional treatment effect on a protocol for ED inpatients to evaluate the efficacy of BPT. We performed the study through statistical analysis of admission and discharge scores.

METHODS

We conducted a case-control study in a hospital ward specialized in eating disorders. Two groups were identified: the control group (TAU; N = 91) and the experimental group (TAU + BPT; N = 91). The experimental group performed BTP activities in addition to the treatment at usual. All patients in both groups had an eating disorder diagnosis (AN, BN, BED and EDNOS/OSFED). Sampling occurred on a time basis and not by randomization. Moreover, all patients admitted in the ED hospital ward in the time frame considered (from end-2009 to mid-2017) were included in the study. BPT activities were introduced in mid-2013 and three psychometric instruments upon entry and discharge were used: Symptom Check List-90 (SCL-90) to measure the general psychopathological state; the Eating Disorder Inventory-3 (EDI-3) to estimate the incidence of personality traits strongly correlated to eating disorders; the body uneasiness test (BUT) to measure the body uneasiness. We performed a pre/post analysis for both groups; we studied the additional effect of the treatment through deltas analysis of the three questionnaires (Δ = assessment at discharge - assessment at the entrance). Data were analyzed using the Student T and the Wilcoxon rank-sum test.

RESULTS

The pre/post analysis showed statistically significant improvement in both conditions (TAU and TAU + BPT) in the general psychopathological state (SCL-90) and in the incidence of personality traits (EDI-3). Improvements in body uneasiness (BUT) were observed only in the experimental group (TAU + BPT). Furthermore, the analysis of the deltas shows more significant improvements in TAU + BPT compared to TAU in all the variables considered.

CONCLUSION

We found an additional effect of the BPT on TAU. The usual ED protocol added with BPT activities showed significantly better clinical results. We have interpreted these results in light of recent developments in the neuroscientific field of body image.

LEVEL OF EVIDENCE

Level II: controlled trial without randomization.

Physiological, emotional and neural responses to visual stimuli in eating disorders: a review

BACKGROUND

Overconcern with food and shape/weight stimuli are central to eating disorder maintenance with attentional biases seen towards these images not present in healthy controls. These stimuli trigger changes in the physiological, emotional, and neural responses in people with eating disorders, and are regularly used in research and clinical practice. However, selection of stimuli for these treatments is frequently based on self-reported emotional ratings alone, and whether self-reports reflect objective responses is unknown.

MAIN BODY

This review assessed the associations across emotional self-report, physiological, and neural responses to both food and body-shape/weight stimuli in people with anorexia nervosa (AN), bulimia nervosa (BN) and binge eating disorder (BED). For food stimuli, either an aversive or lack of physiological effect was generated in people with AN, together with a negative emotional response on neuroimaging, and high subjective anxiety ratings. People with BN showed a positive self-rating, an aversive physiological reaction, and a motivational neural response. In BED, an aversive physiological reaction was found in contrast to motivational/appetitive neural responses, with food images rated as pleasant. The results for shape/weight stimuli showed aversive responses in some physiological modalities, which was reflected in both the emotional and neural responses, but this aversive response was not consistent across physiological studies.

CONCLUSIONS

Shape/weight stimuli are more reliable for use in therapy or research than food stimuli as the impact of these images is more consistent across subjective and objective responses. Care should be taken when using food stimuli due to the disconnect reported in this review.

Moving towards specificity: A systematic review of cue features associated with reward and punishment in anorexia nervosa

Models of anorexia nervosa (AN) posit that symptoms are maintained through deficient reward and enhanced punishment processing. However, theoretical and empirical inconsistencies highlight the need for a more nuanced conceptualization of this literature. Our goal was to comprehensively review the research on reward and punishment responding in AN from a cue-specific lens to determine which stimuli evoke or discourage reward and punishment responses in this population, and, ultimately, what properties these rewarding and punishing cues might share. A systematic review interrogating reward and punishment responses to specific cues yielded articles (n = 92) that examined responses to disorder relevant (e.g., food) and irrelevant (e.g., money) stimuli across self-report, behavioral, and biological indices. Overall, in most studies individuals with AN exhibited aversive responses to cues signaling higher body weights, social contexts, and monetary losses, and appetitive responses to cues for weight loss behaviors and thinness. Findings were more mixed on responses to palatable food and monetary gains. Results highlight that reward and punishment responding in AN are context specific and may be affected by varied stimulus qualities (e.g., predictability, controllability, delay, effort). Increasing specificity in future research on reward and punishment mechanisms in AN will better inform development of precisely-targeted interventions.

Regional cerebral blood flow patterns of change following the own body image exposure in eating disorders: A longitudinal study

Objective

The aim of the present study is to see if the changes in the regional cerebral blood flow (rCBF) experienced by restrictive anorexia nervosa (AR) and bulimia nervosa (BN) patients, following the exposure to their own body image, persist at follow-up.

Methods

Three single photon emission computed tomography (SPECT) were performed on nine patients with a DSM-IV diagnosis of AR, 13 with BP, and 12 controls: at rest, following a neutral stimulus, and after exposure to their previously filmed whole body image. Body dissatisfaction was measured by means of the Body Dissatisfaction Questionnaire (BSQ). One year later the same assessment was repeated.

Results

Following the exposure to their own body image, BN showed an increase in body dissatisfaction, which was associated with the increase in the rCBF of the Right Temporal Area. Those changes persisted at follow-up.

Discussion

More specific long term therapies are needed for the treatment of the averse response showed by ED patients to their own body image exposure that is associated with the hyperactivation of the right temporal area when they are confronted with their whole body image.

Functional neuroimaging in anorexia nervosa: A clinical approach

Aims

To provide a review of the available literature about the functional neuroimaging of anorexia nervosa, and to summarize the possible role of neurobiological factors in its pathogenesis.

Methods

A systematic review of the literature was performed using PubMed and Medline electronic database (1950–September 2009). Eligible studies were restricted to those involving the main parameters of cerebral activity and functional neuroimaging techniques. Findings of the reviewed studies have been grouped on a diagnostic subtype basis, and their comparison has been interpreted in terms of concordance.

Results

We found a high level of concordance among available studies with regard to the presence of frontal, parietal and cingulate functional disturbances in both anorexia nervosa restricting and binge/purging subtypes. Concordance among studies conducted regardless of the anorexia nervosa subtypes suggests an alteration in temporal and parietal functions and striatal metabolism.

Conclusions

The most consistent alterations in anorexia nervosa cerebral activity seem to involve the dorsolateral prefrontal cortex, the inferior parietal lobule, the anterior cingulate cortex and the caudate nucleus. They may affect different neural systems such as the frontal visual system, the attention network, the arousal and emotional processing systems, the reward processing network, and the network for the body schema.

Neural Mechanisms in Eating Behaviors: A Pilot fMRI Study of Emotional Processing

OBJECTIVE

Emotional processing dysfunction evident in eating disorders (ED) such as anorexia nervosa (AN) and bulimia nervosa (BN), is considered relevant to the development and maintenance of these disorders. The purpose of the current functional magnetic resonance imaging (fMRI) study was to pilot a comparison of the activity of the fronto-limbic and fronto-striatal brain areas during an emotion processing task in persons with ED.

METHODS

24 women patients with ED were scanned, while showing emotionally stimulating (pleasant, unpleasant) and neutral images from the International Affective Picture System (IAPS).

RESULTS

During the pleasant condition, significant differences in Dorsolateral Prefrontal Cortex (DLPFC) activations were found with AN participants presenting greater activation compared to BN and ED comorbid groups (EDc) and healthy controls also showing greater activation of this brain area compared to BN and EDc. Left putamen was less activated in EDc compared to both controls (C) and AN. During the unpleasant condition, AN participants showed hyperactivation of the Orbito-frontal Cortex (OFC) when compared to EDc.

CONCLUSION

This study highlights the potential functional relevance of brain areas that have been associated with self-control. These findings should help advance understanding the neural substrate of ED, though they should be considered as preliminary and be cautiously interpreted.

Neural mechanisms of perceptive and affective processing of body stimuli in anorexia nervosa - are there developmental effects?

Different components of body image processing seem to be reflected by different neural mechanisms. A core symptom of Anorexia nervosa (AN) is a disturbance of body image with correlates found on a neural level. The present study focuses on the neural processing of visual body stimuli of different weight categories in adolescent and adult AN patients. Thirty-three adolescents aged 12-18 years (15 AN patients, 18 control participants) and 36 adult women (19 AN patients, 17 control participants) underwent functional magnetic resonance imaging (fMRI) while performing a perceptive and an affective body image task involving photographic stimuli of women belonging to different BMI categories. Differential effects on activation, depending on the BMI of the women shown in the pictures, were found in frontal brain regions, the thalamus, the caudate and the fusiform gyrus. Group effects differentiating between AN patients and control participants were seen mainly in the caudate and insula. No significant developmental effect was seen. During a perceptive task, diminished activation of regions involved in perceptive and evaluative functions as well as emotional reasoning was seen in AN. During an affective task there was a tendency towards activation differences reflecting reduced ability of size estimation and impaired integration of visual and body perception with emotions.

Fractional amplitude of low frequency fluctuation in drug-naïve first-episode patients with anorexia nervosa: A resting-state fMRI study

To characterize the fractional amplitude of low-frequency fluctuation (fALFF) in drug-naïve first-episode female patients with anorexia nervosa (AN) using resting-state functional magnetic resonance imaging (rs-fMRI).Whole brain rs-fMRI data were collected from 7 drug-naïve first-episode female patients with DSM-5 AN and 14 age-matched healthy female controls. fALFF values were calculated and compared between the two groups using a two-sample t test. Correlation analysis between the fALFF values in the entire brain and body mass index (BMI) was performed.Compared with the healthy controls, increased fALFF values were observed in the AN patients in their right hippocampus and left superior frontal gyrus, while decreased fALFF values were observed in their left rectus and left middle occipital gyrus. Moreover, low BMI was significantly associated with decreased fALFF in the left inferior frontal gyrus but increased fALFF in the left calcarine. In particular, the z-standardized fALFF (zfALFF) value of the left rectus was positive associated with BMI.Our findings suggest that spontaneous brain activity in the frontal region, hippocampus and rectus, characterized by fALFF values, was altered in drug-naïve, first-episode female patients with AN.

Body Dissatisfaction Enhances Awareness and Facilitates the Consolidation of Body-Related Words During Rapid Serial Visual Presentation

Attentional biases have received considerable focus in research on cognitive biases and body dissatisfaction (BD). However, most work has focused on spatial allocation of attention. The current two experiments employed a rapid serial visual presentation (RSVP) task to investigate attention bias to body-related words in the temporal domain among young females with high and low BD. During this task, there were two targets presented in the same stimulus stream. The first target was defined as target one (T1) and the second was defined as target 2 (T2). Participants were asked to identify T2 while ignoring T1 in single task mode or identify both targets in the dual task mode. In the current study, Experiment 1 assessed the stimulus-driven attention of body-related stimuli. Participants were required to identify a target of neutral word (T2) as quickly and accurately as possible while ignoring the preceding target (T1) of neutral, fat-, or thin-related words. As expected, we observed spontaneous attentional blink (AB) effects elicited by both fat- and thin-related T1s among participants with high BD, suggesting enhanced awareness of body-related stimuli even when this information does not have to be identified. Such effects did not emerge among participants without BD. Experimental 2 investigated the goal-directed attention of body-related stimuli, during which participants needed to identify both the T1 and neutral T2. Participants with BD showed reduced AB effects after both fat- and thin-related T1, suggesting facilitated consolidation of body-related information in goal-directed attention among participants with BD. These findings have important clinical implications that it provided insight for creating more accurate attention bias modification (ABM) task aiming at reducing and preventing BD among young females.

Brain and Cognitive Development in Adolescents with Anorexia Nervosa: A Systematic Review of fMRI Studies

Anorexia nervosa (AN) is an eating disorder often occurring in adolescence. AN has one of the highest mortality rates amongst psychiatric illnesses and is associated with medical complications and high risk for psychiatric comorbidities, persisting after treatment. Remission rates range from 23% to 33%. Moreover, weight recovery does not necessarily reflect cognitive recovery. This issue is of particular interest in adolescence, characterized by progressive changes in brain structure and functional circuitries, and fast cognitive development. We reviewed existing literature on fMRI studies in adolescents diagnosed with AN, following PRISMA guidelines. Eligible studies had to: (1) be written in English; (2) include only adolescent participants; and (3) use block-design fMRI. We propose a pathogenic model based on normal and AN-related neural and cognitive maturation during adolescence. We propose that underweight and delayed puberty-caused by genetic, environmental, and neurobehavioral factors-can affect brain and cognitive development and lead to impaired cognitive flexibility, which in turn sustains the perpetuation of aberrant behaviors in a vicious cycle. Moreover, greater punishment sensitivity causes a shift toward punishment-based learning, leading to greater anxiety and ultimately to excessive reappraisal over emotions. Treatments combining physiological and neurobehavioral rationales must be adopted to improve outcomes and prevent relapses.

Neural Processing of Disorder-Related Stimuli in Patients with Anorexia Nervosa: A Narrative Review of Brain Imaging Studies

Abnormalities and alterations in brain function are commonly associated with the etiology and maintenance of anorexia nervosa (AN). Different symptom categories of AN have been correlated with distinct neurobiological patterns in previous studies. The aim of this literature review is to provide a narrative overview of the investigations into neural correlates of disorder-specific stimuli in patients with AN. Although findings vary across studies, a summary of neuroimaging results according to stimulus category allows us to account for methodological differences in experimental paradigms. Based on the available evidence, the following conclusions can be made: (a) the neural processing of visual food cues is characterized by increased top-down control, which enables restrictive eating, (b) increased emotional and reward processing during gustatory stimulation triggers disorder-specific thought patterns, (c) hunger ceases to motivate food foraging but instead reinforces disorder-related behaviors, (d) body image processing is related to increased emotional and hedonic reactions, (e) emotional stimuli provoke increased saliency associated with decreased top-down control and (f) neural hypersensitivity during interoceptive processing reinforces avoidance behavior. Taken together, studies that investigated symptom-specific neural processing have contributed to a better understanding of the underlying mechanisms of AN.

Anorexia Nervosa and a Lost Emotional Self: A Psychological Formulation of the Development, Maintenance, and Treatment of Anorexia Nervosa

In this paper, we argue that Anorexia Nervosa (AN) can be explained as arising from a 'lost sense of emotional self.' We begin by briefly reviewing evidence accumulated to date supporting the consensus that a complex range of genetic, biological, psychological, and socio-environmental risk and maintenance factors contribute to the development and maintenance of AN. We consider how current interventions seek to tackle these factors in psychotherapy and potential limitations. We then propose our theory that many risk and maintenance factors may be unified by an underpinning explanation of emotional processing difficulties leading to a lost sense of 'emotional self.' Further, we discuss how, once established, AN becomes 'self-perpetuating' and the 'lost sense of emotional self' relentlessly deepens. We outline these arguments in detail, drawing on empirical and neuroscientific data, before discussing the implications of this model for understanding AN and informing clinical intervention. We argue that experiential models of therapy (e.g., emotion-focused therapy; schema therapy) be employed to achieve emergence and integration of an 'emotional self' which can be flexibly and adaptively used to direct an individual's needs and relationships. Furthermore, we assert that this should be a primary goal of therapy for adults with established AN.

Conceptualizing body dissatisfaction in eating disorders within a self-discrepancy framework: a review of evidence

Body dissatisfaction, the negative subjective evaluation of one's body, is associated with many negative psychological and physical health consequences. One conceptualization of body dissatisfaction includes an experience of discrepancy between perceived actual and ideal body shapes. This paper reviews the literature on three facets of body dissatisfaction from the framework of self-discrepancy theory: perceptions of current weight, ideal body weight, and the relative importance of conforming to ideals. We review components of body dissatisfaction among healthy individuals and eating-disordered individuals. We also address the conceptualization's relationship among body dissatisfaction, weight history, and dieting to expand the impact of body dissatisfaction research and to provide more information on the nature and treatment of eating disorders.

Self and other body perception in anorexia nervosa: The role of posterior DMN nodes

OBJECTIVES

Body image distortion is a core symptom of anorexia nervosa (AN), which involves alterations in self- (and other's) evaluative processes arising during body perception. At a neural level, self-related information is thought to rely on areas of the so-called default mode network (DMN), which, additionally, shows prominent synchronised activity at rest.

METHODS

Twenty female patients with AN and 20 matched healthy controls were scanned using magnetic resonance imaging when: (a) viewing video clips of their own body and another's body; (b) at rest. Between-group differences within the DMN during task performance were evaluated and further explored for task-related and resting-state-related functional connectivity alterations.

RESULTS

AN patients showed a hyperactivation of the dorsal posterior cingulate cortex during their own-body processing but a response failure to another's body processing at the precuneus and ventral PCC. Increased task-related connectivity was found between dPCC-dorsal anterior cingulate cortex and precuneus-mid-temporal cortex. Further, AN patients showed decreased resting-state connectivity between the dPCC and the angular gyrus.

CONCLUSIONS

The PCC and the precuneus are suggested as key components of a network supporting self-other-evaluative processes implicated in body distortion, while the existence of DMN alterations at rest might reflect a sustained, task-independent breakdown within this network in AN.

All in the mind? The neural correlates of unexplained physical symptoms

Physical symptoms with no medical explanation are commonly experienced by healthy people and those attending clinics. Psychiatrists see such patients in liaison settings and clinics for those with psychotic and affective disorders. The pathophysiology remains obscure; physical investigations are usually performed to exclude pathology rather than elucidate dysfunction. However, modern neuroimaging has allowed the study of nervous system structure and function. Although there are few diagnostically specific findings, patterns of association have emerged: where action is impeded (certain forms of conversion disorder and chronic fatigue syndrome) frontal systems of the brain are often implicated; when subjective awareness of the body is disturbed (passivity phenomena and anorexia nervosa) temporo-parietal cortices appear to be dysfunctional. The caudate nuclei (components of the frontal executive circuit) are implicated in a variety of syndromes (including body dysmorphic disorder, somatisation and chronic fatigue). The brain may be viewed as a cognitive neurobiological entity, crucially oriented towards action (for survival). Psychiatric syndromes that have an impact on bodily awareness signal dysfunction within systems representing that body and its performance in time and space.

Processing and regulation of negative emotions in anorexia nervosa: An fMRI study

Theoretical models and recent advances in the treatment of anorexia nervosa (AN) have increasingly focused on the role of alterations in the processing and regulation of emotions. To date, however, our understanding of these changes is still limited and reports of emotional dysregulation in AN have been based largely on self-report data, and there is a relative lack of objective experimental evidence or neurobiological data. The current functional magnetic resonance imaging (fMRI) study investigated the hemodynamic correlates of passive viewing and voluntary downregulation of negative emotions by means of the reappraisal strategy detachment in AN patients. Detachment is regarded as adaptive regulation strategy associated with a reduction in emotion-related amygdala activity and increased recruitment of prefrontal brain regions associated with cognitive control processes. Emotion regulation efficacy was assessed via behavioral arousal ratings and fMRI activation elicited by an established experimental paradigm including negative images. Participants were instructed to either simply view emotional pictures or detach themselves from feelings triggered by the stimuli. The sample consisted of 36 predominantly adolescent female AN patients and a pairwise age-matched healthy control group. Behavioral and neuroimaging data analyses indicated a reduction of arousal and amygdala activity during the regulation condition for both patients and controls. However, compared with controls, individuals with AN showed increased activation in the amygdala as well as in the right dorsolateral prefrontal cortex (dlPFC) during the passive viewing of aversive compared with neutral pictures. These results extend previous findings indicative of altered processing of salient emotional stimuli in AN, but do not point to a general deficit in the voluntary regulation of negative emotions. Increased dlPFC activation in AN during passive viewing of negative stimuli is in line with the hypothesis that the disorder may be characterized by excessive self-control. Taken together, the data seem to suggest that reappraisal via detachment may be an effective strategy to reduce negative arousal for individuals with AN.

Dissatisfaction with own body makes patients with eating disorders more sensitive to pain

Body image represents a multidimensional concept including body image evaluation and perception of body appearance. Disturbances of body image perception are considered to be one of the central aspects of anorexia nervosa and bulimia nervosa. There is growing evidence that body image distortion can be associated with changes in pain perception. The aim of our study was to examine the associations between body image perception, body dissatisfaction, and nociception in women with eating disorders and age-matched healthy control women. We measured body dissatisfaction and pain sensitivity in 61 patients with Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition diagnoses of eating disorders (31 anorexia nervosa and 30 bulimia nervosa) and in 30 healthy women. Thermal pain threshold latencies were evaluated using an analgesia meter and body image perception and body dissatisfaction were assessed using Anamorphic Micro software (digital pictures of their own body distorted into larger-body and thinner-body images). Patients with eating disorders overestimated their body size in comparison with healthy controls, but the two groups did not differ in body dissatisfaction. In anorexia and bulimia patient groups, body dissatisfaction (calculated in pixels as desired size/true image size) correlated with pain threshold latencies (r=0.55, p=0.001), while between body image perception (determined as estimation size/true image size) and pain threshold, no correlation was found. Thus, we demonstrated that in patients with eating disorders, pain perception is significantly associated with emotional contrary to sensory (visual) processing of one’s own body image. The more the patients desired to be thin, the more pain-sensitive they were. Our findings based on some shared mechanisms of body dissatisfaction and pain perception support the significance of negative emotions specific for eating disorders and contribute to better understanding of the psychosomatic characteristics of this spectrum of illnesses.

Micronutrient Status in 153 Patients with Anorexia Nervosa

Micronutrient status in Anorexia Nervosa (AN) has been poorly documented and previous data are often contradictory. We aimed to assess micronutrient status in a large population of AN patients. The relationships between micronutrient status and body composition were also determined. Anthropometric, biochemical parameters and body composition data were collected at referral in 153 patients with AN (28.5 ± 11 years). At least one trace element deficit was observed in almost half of patients; the most frequent was selenium deficit (40% of patients). At least one vitamin deficit was observed in 45.7% of patients, mostly vitamin A and B9. Albumin, transthyretin and CRP were within normal range in most patients. No correlations were found between body composition and micronutrient status. Our study suggests that micronutrient status is often altered in AN patients, which may contribute to neuropsychiatric dysfunction. Monitoring of micronutrients and correction of deficits should be included in the routine care of AN patients.

Altered microstructure of brain white matter in females with anorexia nervosa: a diffusion tensor imaging study

OBJECTIVE

Structural studies have reported anorexia nervosa (AN) patients with abnormal gray matter in several brain regions and dysfunction in some connected neural circuits. However, the role of white matter (WM) in AN patients has rarely been investigated. The present study aimed to assess alterations in WM microstructure of the entire brain in females with AN using a voxel-based method on diffusion tensor imaging (DTI) data.

MATERIALS AND METHODS

The study enrolled 8 female patients with AN and 14 age-matched females as controls (CW). The DTI data was collected from each subject to calculate the fractional anisotropy (FA) maps of the whole brain by the DTI-Studio software. Subsequently, a 2-sample t-test (P<0.05, corrected) was performed to detect the difference in FA maps of AN and CW group, and a Pearson's correlation analyzed the relationship between mean FA value of brain regions and body mass index (BMI).

RESULTS

Compared with CW, AN patients revealed a significant decrease in FA maps in the left superior frontal gyrus, medial frontal gyrus, anterior cingulate cortex, middle frontal gyrus, inferior frontal gyrus, thalamus, and bilateral insula. Moreover, significantly positive correlations were established between the mean FA value of the left inferior frontal gyrus, insula as well as thalamus and BMI in AN patients.

CONCLUSIONS

Our findings supported the presence of WM abnormality in patients with AN. The significant differences of FA maps, in patients with AN, were associated with their aberrant BMI. The results further improved our understanding of the pathophysiological mechanisms underlying AN.

My Body Looks Like That Girl's: Body Mass Index Modulates Brain Activity during Body Image Self-Reflection among Young Women

Body image distress or body dissatisfaction is one of the most common consequences of obesity and overweight. We investigated the neural bases of body image processing in overweight and average weight young women to understand whether brain regions that were previously found to be involved in processing self-reflective, perspective and affective components of body image would show different activation between two groups. Thirteen overweight (O-W group, age = 20.31±1.70 years) and thirteen average weight (A-W group, age = 20.15±1.62 years) young women underwent functional magnetic resonance imaging while performing a body image self-reflection task. Among both groups, whole-brain analysis revealed activations of a brain network related to perceptive and affective components of body image processing. ROI analysis showed a main effect of group in ACC as well as a group by condition interaction within bilateral EBA, bilateral FBA, right IPL, bilateral DLPFC, left amygdala and left MPFC. For the A-W group, simple effect analysis revealed stronger activations in Thin-Control compared to Fat-Control condition within regions related to perceptive (including bilateral EBA, bilateral FBA, right IPL) and affective components of body image processing (including bilateral DLPFC, left amygdala), as well as self-reference (left MPFC). The O-W group only showed stronger activations in Fat-Control than in Thin-Control condition within regions related to the perceptive component of body image processing (including left EBA and left FBA). Path analysis showed that in the Fat-Thin contrast, body dissatisfaction completely mediated the group difference in brain response in left amygdala across the whole sample. Our data are the first to demonstrate differences in brain response to body pictures between average weight and overweight young females involved in a body image self-reflection task. These results provide insights for understanding the vulnerability to body image distress among overweight or obese young females.

Alterations in emotion generation and regulation neurocircuitry in depression and eating disorders: A comparative review of structural and functional neuroimaging studies

Major depression and eating disorders (EDs) are highly co-morbid and may share liability. Impaired emotion regulation may represent a common etiological or maintaining mechanism. Research has demonstrated that depressed individuals and individuals with EDs exhibit impaired emotion regulation, with these impairments being associated with changes in brain structure and function. The goal of this review was to evaluate findings from neuroimaging studies of depression and EDs to determine whether there are overlapping alterations in the brain regions known to be involved in emotion regulation, evidence of which would aid in the diagnosis and treatment of these conditions. Our review of the literature suggests that depression and EDs exhibit common structural and functional alterations in brain regions involved in emotion regulation, including the amygdala, ventral striatum and nucleus accumbens, anterior cingulate cortex, insula, and dorsolateral prefrontal cortex. We present preliminary support for a shared etiological mechanism. Future studies should consider manipulating emotion regulation in a sample of individuals with depression and EDs to better characterize abnormalities in these brain circuits.

Posturographic destabilization in eating disorders in female patients exposed to body image related phobic stimuli

Human postural control is dependent on the central integration of vestibular, visual and proprioceptive inputs. Psychological states can affect balance control: anxiety, in particular, has been shown to influence balance mediated by visual stimuli. We hypothesized that patients with eating disorders would show postural destabilization when exposed to their image in a mirror and to the image of a fashion model representing their body ideal in comparison to body neutral stimuli. Seventeen females patients attending a day centre for the treatment of eating disorders were administered psychometric measures of body dissatisfaction, anxiety, depression and underwent posturographic measures with their eyes closed, open, watching a neutral stimulus, while exposed to a full length mirror and to an image of a fashion model corresponding to their body image. Results were compared to those obtained by eighteen healthy subjects. Eating disordered patients showed higher levels of body dissatisfaction and higher postural destabilization than controls, but this was limited to the conditions in which they were exposed to their mirror image or a fashion model image. Postural destabilization under these conditions correlated with measures of body dissatisfaction. In eating disordered patients, body related stimuli seem to act as phobic stimuli in the posturographic paradigm used. If confirmed, this has the potential to be developed for diagnostic and therapeutic purposes.

The role of body image and self-perception in anorexia nervosa: the neuroimaging perspective

Anorexia nervosa is a severe psychiatric illness characterized by intense fear of gaining weight, relentless pursuit of thinness, deep concerns about food and a pervasive disturbance of body image. Functional magnetic resonance imaging tries to shed light on the neurobiological underpinnings of anorexia nervosa. This review aims to evaluate the empirical neuroimaging literature about self-perception in anorexia nervosa. This narrative review summarizes a number of task-based and resting-state functional magnetic resonance imaging studies in anorexia nervosa about body image and self-perception. The articles listed in references were searched using electronic databases (PubMed and Google Scholar) from 1990 to February 2016 using specific key words. All studies were reviewed with regard to their quality and eligibility for the review. Differences in brain activity were observed using body image perception and body size estimation tasks showing significant modifications in activity of specific brain areas (extrastriate body area, fusiform body area, inferior parietal lobule). Recent studies highlighted the role of emotions and self-perception in anorexia nervosa and their neural substrate involving resting-state networks and particularly frontal and posterior midline cortical structures within default mode network and insula. These findings open new horizons to understand the neural substrate of anorexia nervosa.

Amygdala alterations during an emotional conflict task in women recovered from anorexia nervosa

The pathophysiology of anorexia nervosa (AN) is not completely understood, but research suggests that alterations in brain circuits related to cognitive control and emotion are central. The aim of this study was to explore neural responses to an emotional conflict task in women recovered from AN. Functional magnetic resonance imaging was used to measure neural responses to an emotional conflict task in 22 women recovered from AN and 21 age-matched healthy controls. The task involved categorizing affective faces while ignoring affective words. Face and word stimuli were either congruent (non-conflict) or incongruent (conflict). Brain responses to emotional conflict did not differ between groups. However, in response to emotional non-conflict, women recovered from AN relative to healthy controls showed significantly less activation in the bilateral amygdala. Specifically, while emotional non-conflict evoked significant activations of the amygdala in healthy controls, recovered AN women did not show such activations. Similar significant group differences were also observed in the hippocampus and basal ganglia. These results suggest that women recovered from AN are characterized by alterations within emotion-related brain circuits. Recovered women's absence of amygdala and hippocampus activation during non-conflict trials possibly reflects an impaired ability to process emotional significant stimuli.

Targeting Neural Endophenotypes of Eating Disorders with Non-invasive Brain Stimulation

The term "eating disorders" (ED) encompasses a wide variety of disordered eating and compensatory behaviors, and so the term is associated with considerable clinical and phenotypic heterogeneity. This heterogeneity makes optimizing treatment techniques difficult. One class of treatments is non-invasive brain stimulation (NIBS). NIBS, including repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), are accessible forms of neuromodulation that alter the cortical excitability of a target brain region. It is crucial for NIBS to be successful that the target is well selected for the patient population in question. Targets may best be selected by stepping back from conventional DSM-5 diagnostic criteria to identify neural substrates of more basic phenotypes, including behavior related to rewards and punishment, cognitive control, and social processes. These phenotypic dimensions have been recently laid out by the Research Domain Criteria (RDoC) initiative. Consequently, this review is intended to identify potential dimensions as outlined by the RDoC and the underlying behavioral and neurobiological targets associated with ED. This review will also identify candidate targets for NIBS based on these dimensions and review the available literature on rTMS and tDCS in ED. This review systematically reviews abnormal neural circuitry in ED within the RDoC framework, and also systematically reviews the available literature investigating NIBS as a treatment for ED.

Interacting Neural Processes of Feeding, Hyperactivity, Stress, Reward, and the Utility of the Activity-Based Anorexia Model of Anorexia Nervosa

Anorexia nervosa (AN) is a psychiatric illness with minimal effective treatments and a very high rate of mortality. Understanding the neurobiological underpinnings of the disease is imperative for improving outcomes and can be aided by the study of animal models. The activity-based anorexia rodent model (ABA) is the current best parallel for the study of AN. This review describes the basic neurobiology of feeding and hyperactivity seen in both ABA and AN, and compiles the research on the role that stress-response and reward pathways play in modulating the homeostatic drive to eat and to expend energy, which become dysfunctional in ABA and AN.

Alterations in Activity, Volume, and Connectivity of Body-Processing Brain Areas in Anorexia Nervosa

Body image disturbance is one of the main symptoms of eating disorders; however, the neural basis of this phenomenon is not well understood yet. In the present paper, we review studies investigating the neuronal correlates of visual body perception in anorexia nervosa. We first focus on the well-known parietal lobe contribution to body image processing and its malfunction. Additionally, we focus on the contribution and involvement of the extrastriate and fusiform body area in eating disorders, especially anorexia nervosa. The summarized studies provide first evidence for a reduced activity, volume, and connectivity in brain areas involved and specialized in the visual processing of human bodies. In general, the reviewed studies provide evidence for abnormalities in body-processing brain areas in anorexia nervosa, indicating two structures in the brain that are involved: early stages of body processing in the visual extrastriate cortex and later stages in the parietal cortex.

Brain structure alterations associated with weight changes in young females with anorexia nervosa: a case series

Structural brain changes associated with starvation and clinical measurements were explored in four females with anorexia nervosa with different clinical course, at baseline and 1-year follow-up, after receiving intensive inpatient treatment at a specialized eating disorder unit. Global volume alterations were associated with weight changes. Regional volume alterations were also associated with weight changes, with the largest changes occurring in the nucleus accumbens, amygdala, pallidum, and putamen. Largest changes in cortical thickness occurred in the frontal and temporal lobes. The results are preliminary; however, they show that fluctuations in weight are associated with brain volume alterations, especially gray matter. We suggest that these parts of the brain are vulnerable to starvation and malnutrition, and could be a part of the pathophysiology of AN.

Stress exposure, food intake and emotional state

This manuscript summarizes the proceedings of the symposium entitled, "Stress, Palatable Food and Reward", that was chaired by Drs. Linda Rinaman and Yvonne Ulrich-Lai at the 2014 Neurobiology of Stress Workshop held in Cincinnati, OH. This symposium comprised research presentations by four neuroscientists whose work focuses on the biological bases for complex interactions among stress, food intake and emotion. First, Dr Ulrich-Lai describes her rodent research exploring mechanisms by which the rewarding properties of sweet palatable foods confer stress relief. Second, Dr Stephanie Fulton discusses her work in which excessive, long-term intake of dietary lipids, as well as their subsequent withdrawal, promotes stress-related outcomes in mice. Third, Dr Mark Wilson describes his group's research examining the effects of social hierarchy-related stress on food intake and diet choice in group-housed female rhesus macaques, and compared the data from monkeys to results obtained in analogous work using rodents. Finally, Dr Gorica Petrovich discusses her research program that is aimed at defining cortical-amygdalar-hypothalamic circuitry responsible for curbing food intake during emotional threat (i.e. fear anticipation) in rats. Their collective results reveal the complexity of physiological and behavioral interactions that link stress, food intake and emotional state, and suggest new avenues of research to probe the impact of genetic, metabolic, social, experiential and environmental factors on these interactions.

Social insecurity in relation to orbitofrontal activity in patients with eating disorders: a near-infrared spectroscopy study

BACKGROUND

Functional neuroimaging techniques are widely used to elucidate changes in brain activity, and various questionnaires are used to investigate psychopathological features in patients with eating disorders (ED). It is well known that social skills and interpersonal difficulties are strongly associated with the psychopathology of patients with ED. However, few studies have examined the association between brain activity and social relationships in patients with ED, particularly in patients with extremely low body weight.

METHODS

In this study, 22-channel near-infrared spectroscopy was used to quantify regional hemodynamic changes during a letter fluency task (LFT) in 20 female patients with ED with a mean body mass index of 14.0 kg/m(2) and 31 female controls (CTLs). Symptoms were assessed using the Eating Disorder Inventory-2 and Beck Depression Inventory. We hypothesized that frontal activity in patients with ED would be lower than in CTLs and would show different correlations with psychopathological features compared with CTLs.

RESULTS

The LFT performance and score on the social insecurity subscale of the Eating Disorder Inventory-2 were significantly higher in the ED group than in the CTL group. The mean change in oxygenated hemoglobin (oxy-Hb) in bilateral frontal regions during the LFT was significantly smaller in the ED group than in the CTL group. Social insecurity score was positively correlated with the concentration of oxy-Hb in the bilateral orbitofrontal cortex in the ED group but not in the CTL group.

CONCLUSIONS

These results suggest that activity of the orbitofrontal cortex is associated with social insecurity and disturbed in patients with ED. Therefore, disturbed orbitofrontal cortex activity may underlie the lack of insight and social isolation that is characteristic of patients with ED.

Body image disturbance in children and adolescents with eating disorders. Current evidence and future directions

Body image is multifaceted and incorporates perceptual, affective, and cognitive components as well as behavioral features. Only few studies have examined the character of body-image disturbance in children/adolescents with eating disorders. It is unknown whether body-image disturbances in children/adolescent with eating disturbances are comparable to those of adult patients with eating disorders. Body-image disturbance might differ quantitatively and qualitatively according to the cognitive developmental status and the age of the individual. This paper provides an overview of the current evidence for body-image disturbance in children/adolescents with eating disorders, and how they compare with those adults with eating disorders. Current evidence indicates that older adolescent patients show similar deficits as adult patients with eating disorders, in particular for the attitudinal body-image component. However, evidence for a perceptual body-image disturbance in adolescent patients, in particular anorexia nervosa, is not conclusive. Reliable statements for childhood can hardly be made because clinical studies are not available. Investigations of body-image disturbance in children have focused on the predictive value for eating disorders. Limitations of the current evidence are discussed, and future directions for research and therapy are indicated.

Gender differences in the neural underpinning of perceiving and appreciating the beauty of the body

Although previous studies have suggested a certain degree of right hemisphere dominance for the response of extrastriate body area (EBA) during body perception, recent evidence suggests that this functional lateralization may differ between men and women. It is unknown, however, whether and how gender differences in body perception affect appreciating the beauty of the body of conspecifics. Here, we applied five 10-Hz repetitive transcranial magnetic stimulation (rTMS) pulses over left and right EBA and over the vertex to investigate the contribution of visual body representations in the two hemispheres on esthetic body perception. Female and male healthy volunteers were requested to judge how much they liked opposite- and same-gender virtual model bodies or to judge their weight, thus allowing us to compare the effects of right- and left-EBA rTMS on esthetic (liking) and perceptual (weight) judgments of human bodies. The analysis of the esthetic judgments provided by women revealed that right-EBA rTMS increased the liking judgments of opposite- but not same-gender models, as compared to both vertex and left EBA stimulation. Conversely, in men the liking judgments of opposite-gender models decreased after virtual disruption of both right and left EBA as compared to vertex stimulation. Crucially, no significant effect was found for the perceptual task, showing that left- and right-EBA rTMS did not affect weight perception. Our results provide evidence of gender difference in the hemispheric asymmetry of EBA in the esthetic processing of human bodies, with women showing stronger right hemisphere dominance in comparison with men.

The neurobiology of anorexia nervosa: a systematic review

OBJECTIVE

Recent advances in neuroimaging techniques have enabled a better understanding of the neurobiological underpinnings of anorexia nervosa (AN). The aim of this paper was to summarise our current understanding of the neurobiology of AN.

METHODS

The literature was searched using the electronic databases PubMed and Google Scholar, and by additional hand searches through reference lists and specialist eating disorders journals. Relevant studies were included if they were written in English, only used human participants, had a specific AN group, used clinical populations of AN, group comparisons were reported for AN compared to healthy controls and not merely AN compared to other eating disorders or other psychiatric groups, and were not case studies.

RESULTS

The systematic review summarises a number of structural and functional brain differences which are reported in individuals with AN, including differences in neurotransmitter function, regional cerebral blood flow, glucose metabolism, volumetrics and the blood oxygen level dependent response.

CONCLUSION

Several structural and functional differences have been reported in AN, some of which reverse and others which persist following weight restoration. These findings have important implications for our understanding of the neurobiological underpinnings of AN, and further research in this field may provide new direction for the development of more effective treatments.

The neural basis of optimism and pessimism

Our survival and wellness require a balance between optimism and pessimism. Undue pessimism makes life miserable; however, excessive optimism can lead to dangerously risky behaviors. A review and synthesis of the literature on the neurophysiology subserving these two worldviews suggests that optimism and pessimism are differentially associated with the two cerebral hemispheres. High self-esteem, a cheerful attitude that tends to look at the positive aspects of a given situation, as well as an optimistic belief in a bright future are associated with physiological activity in the left-hemisphere (LH). In contrast, a gloomy viewpoint, an inclination to focus on the negative part and exaggerate its significance, low self-esteem as well as a pessimistic view on what the future holds are interlinked with neurophysiological processes in the right-hemisphere (RH). This hemispheric asymmetry in mediating optimistic and pessimistic outlooks is rooted in several biological and functional differences between the two hemispheres. The RH mediation of a watchful and inhibitive mode weaves a sense of insecurity that generates and supports pessimistic thought patterns. Conversely, the LH mediation of an active mode and the positive feedback it receives through its motor dexterity breed a sense of confidence in one's ability to manage life's challenges, and optimism about the future.