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

Sex differences in the association of postural control with indirect measures of body representations

Besides anthropometric variables, high-order body representations have been hypothesised to influence postural control. However, this has not been directly tested before. Moreover, some studies indicate that sex moderates the relationship of anthropometry and postural control. Therefore, as a proof of concept we investigated the association of body representations with postural control as well as the influence of participants’ sex/gender. Body image measures were assessed with a figural drawing task. Body schema was tested by a covert and an overt task. Body sway was measured during normal bipedal quiet standing with eyes closed (with/without neck extended). Statistical analysis consisted of hierarchical multiple linear regressions with the following regression steps: (1) sensory condition, (2) sex/gender, (3) age, (4) anthropometry, (5) body schema, (6) body image, (7) sex/gender-interactions. Across 36 subjects (19 females), body schema was significantly associated with body sway variability and open-loop control, in addition to commonly known influencing factors, such as sensory condition, gender, age and anthropometry. While in females, also body image dissatisfaction substantially was associated with postural control, this was not the case in males. Sex differences and possible causes why high-order body representations may influence concurrent sensorimotor control of body sway are discussed.

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.

Body Size Judgments at 17 ms: Evidence From Perceptual and Attitudinal Body Image Indexes

Evidence related to temporal control for stimuli presentation of whole-body image is generally associated with attentional bias to ideal thin bodies. Few studies present evidence concerning whole-body stimuli recognition during fast visual exposure intervals. The aim of this study was to evaluate the accuracy and reaction times for the judgment of different sized body silhouettes presented at 17 ms in a non-clinical sample. Thirty-one participants were divided in attitudinal and perceptual body image groups based on Figure Rating Scale output and performed two experiments. First experiment assessed perception and the clarity of visual experience for human and non-human body stimuli at 17 ms. A general accuracy of 69.17% was registered with no differences between perceptual and attitudinal body image groups. These results indicated that the way participants perceive their own bodies does not influence the recognition of general visual silhouette stimuli. It was also observed that the clarity of visual experience is positively correlated to stimuli recognition accuracy. In the second experiment participants had to respond in a seven-point Likert scale if the presented image of body silhouettes were bigger, equal or thinner than their own bodies. Trials were divided in two blocks based on spatial rotation, half at 0° and half at 180°. General accuracy for body silhouettes recognition was 41.1%. Greater accuracy recognition for regular positioned stimuli was observed. Attitudinal dimension of body image was not a predictor of differential performance whereas perceptual body image groups recorded contrasting recognition performance. Distorted body image participants presented higher accuracy than undistorted body image participants, with greater accuracy to thinner silhouette figures. Women had significantly higher overall accuracy than men considering both experimental blocks. When comparing the cumulative accuracy curves across experimental trials, an exposure effect was registered only for the first experiment. Results showed that body silhouette stimuli were judged in a fast exposure interval with differential accuracy rates only for perceptual body image groups. Such evidence signals that conscious body image can be associated to implicit detection of visual human body stimuli. Future studies should further test how traditional explicit body image outputs perform within experimental approaches.

Expand your body when you look at yourself: The role of the posture in a mirror exposure task

Mirror exposure (ME) is one of the main components of the treatment of patients with eating disorders symptomatology and it has shown its effectiveness in improving several outcomes (e.g., body dissatisfaction). However, the study as to what body posture should be adopted to maximize its effectiveness has been neglected. From embodied cognition and emotion theories, the adoption of an expansive (vs. contractive) body posture has been associated with positive changes in cognitive and emotional responses. The objective of this study was to analyze the effect of adopting an expansive (vs. contractive) posture before an ME task on body-related emotions and cognitions, as well as to analyze the possible moderator and mediator variables of these relationships. The sample was composed of 68 women (age: M = 21.74, SD = 3.12) with high scores on body dissatisfaction. Participants were randomly assigned to the expansive or contractive condition, where the openness of the arms/legs and the back position were manipulated. Posture was monitored by an electronic device and participants filled out several self-reported measures. ANCOVAs, moderation, mediation, and moderated mediated analyses were performed. Results showed that women in the expansive condition showed higher positive emotions after the ME. Moreover, exploratory analyses showed that adopting an expansive posture improved positive emotions, leading to improvements in negative emotions, body image satisfaction, and appraisal of the person’s own body. Psychological interventions should explore the value of holding an expansive posture before the ME in women with body dissatisfaction.