Body representations and cognitive ontology: Drawing the boundaries of the body image

The distinction between body image and body schema has been incredibly influential in cognitive neuroscience. Recently, researchers have begun to speculate about the relationship between these representations (Gadsby, 2017, 2018; Pitron & de Vignemont, 2017; Pitron et al., 2018). Within this emerging literature, Pitron et al. (2018) proposed that the long-term body image and long-term body schema co-construct one another, through a process of reciprocal interaction. In proposing this model, they make two assumptions: that the long-term body image incorporates the spatial characteristics of tools, and that it is distorted in the case of Alice in wonderland syndrome. Here, I challenge these assumptions, with a closer examination of what the term “long-term body image” refers to. In doing so, I draw out some important taxonomic principles for research into body representation.     

Visuo-tactile congruency influences the body schema during full body ownership illusion

Previous research showed that full body ownership illusions in virtual reality (VR) can be robustly induced by providing congruent visual stimulation, and that congruent tactile experiences provide a dispensable extension to an already established phenomenon. Here we show that visuo-tactile congruency indeed does not add to already high measures for body ownership on explicit measures, but does modulate movement behavior when walking in the laboratory. Specifically, participants who took ownership over a more corpulent virtual body with intact visuo-tactile congruency increased safety distances towards the laboratory’s walls compared to participants who experienced the same illusion with deteriorated visuo-tactile congruency. This effect is in line with the body schema more readily adapting to a more corpulent body after receiving congruent tactile information. We conclude that the action-oriented, unconscious body schema relies more heavily on tactile information compared to more explicit aspects of body ownership.     

Normal body scheme and absent phantom limb experience in amputees while dreaming

While dreaming amputees often experience a normal body image and the phantom limb may not be present. However, dreaming experiences in amputees have mainly been collected by questionnaires. We analysed the dream reports of amputated patients with phantom limb collected after awakening from REM sleep during overnight videopolysomnography (VPSG). Six amputated patients underwent overnight VPSG study. Patients were awakened during REM sleep and asked to report their dreams. Three patients were able to deliver an account of a dream. In all dreaming recalls, patients reported that the amputated limbs were intact and completely functional and they no longer experienced phantom limb sensations. Phantom limb experiences, that during wake result from a conflict between a pre-existing body scheme and the sensory information on the missing limb, were suppressed during sleep in our patients in favour of the image of an intact body accessed during dream.     

Locomotor body scheme

The concept of body schema has been introduced and widely discussed in the literature to explain various clinical observations and distortions in the body and space representation. Here we address the role of body schema related information in multi-joint limb motion. The processing of proprioceptive information may differ significantly in static and dynamic conditions since in the latter case the control system may employ specific dynamic rules and constraints. Accordingly, the perception of movement, e.g., estimation of step length and walking distance, may rely on a priori knowledge about intrinsic dynamics of limb segment motion and inherent relationships between gait parameters and body proportions. The findings are discussed in the general framework of space and body movement representation and suggest the existence of a dynamic locomotor body schema used for controlling step length and path estimation.     

Perfectionistic self-presentation, body image, and eating disorder symptoms

A specific model for eating disorder symptoms involving perfectionistic self-presentation and two different moderators (i.e., body image evaluation and body image investment) was tested. Participants completed measures of perfectionistic self-presentation, body image dysfunction, and eating disorder symptoms. Findings indicated that all three dimensions of perfectionistic self-presentation were associated with eating disorder symptoms. Results also showed that perfectionistic self-presentation predicted eating disorder symptoms in women who were dissatisfied with their bodies, but that it did not predict eating problems in women who liked their bodies and felt there was little or no discrepancy between their actual and ideal appearances. Body image investment did not moderate the relationship between perfectionistic self-presentation and eating disorder symptoms, suggesting that ego-involvement alone is insufficient to promote eating disturbance in the context of perfectionism. The importance of self-presentation components of perfectionism and specific body image difficulties in predicting eating disorder symptoms are discussed.     

Appearance-based exercise motivation moderates the relationship between exercise frequency and positive body image

Individuals with a positive body image appreciate their bodies, hold an internal perspective of their bodies, and are satisfied with the functionality of their bodies. Research shows that positive body image is more complex than the absence of body dissatisfaction. Although exercise reduces women's body dissatisfaction, very little research has explored how, or even whether, exercise is associated with positive body image. Therefore, we examined whether exercise frequency was positively related to three aspects of positive body image (body appreciation, internal body orientation, and functional body satisfaction) among 321 college women. Appearance-based exercise motivation (the extent exercise is pursued to influence weight or shape) was hypothesized to moderate these associations. Hierarchical moderated regression analyses showed that exercise frequency was related to higher positive body image, but high levels of appearance-based exercise motivation weakened these relationships. Thus, messages promoting exercise need to de-emphasize weight loss and appearance for positive body image.     

An assessment of body appreciation and its relationship to sexual function in women

Objectification theory posits internalization of an observer's gaze may negatively impact women's feelings about their bodies, which may subsequently affect their sexual function. Subjective body image and body size (i.e., body mass index [BMI]) have mixed relationships to women's sexuality, but assessment of positive body image as a sign of resistance to objectification has not been researched. This study explored relations between body appreciation and sexual function in women and assessed whether body size impacted this relationship. Cross-sectional data were collected online from 247 women, ages 18 to 58. Body appreciation scores were modestly negatively correlated with BMI, while BMI was not related to sexual function scores. After controlling for sexual orientation, partner status, and age, body appreciation predicted the arousal, orgasm, and satisfaction aspects of sexual function. Practitioners’ encouragement of body appreciation may improve sexual function in a way that encouraging a reduction in body size may not.     

Body image importance and body dissatisfaction among indigenous Australian adolescents

Despite their elevated risk of health problems and a propensity to be more overweight or underweight relative to the other members of the Australian population, there has been no previous investigation of body image concerns among Indigenous Australians. In this study we investigated the level of body image importance and body image dissatisfaction among 19 rural Indigenous adolescents (7 males, 12 females) and 28 urban Indigenous adolescents (15 males and 13 females). Our hypotheses that there would be gender differences in body image importance and body image satisfaction were not generally supported. However, males placed more importance on muscle size and strength than females, and rural participants placed more importance on weight than urban participants. Comparison to existing data obtained from Caucasian adolescents suggested that Indigenous youth may be less concerned and dissatisfied with body weight and shape. These results are discussed in relation to findings from studies of non-Indigenous adolescents, and Indigenous health issues. The limitations of the current study and the need for further studies are also discussed.     

身体表征的分离:二分解释模型及其证据

身体表征是一种内部结构,它具有追踪身体状态并对其进行编码的功能。这种结构可以对身体进行错误的表征,并可以从身体中分离出来。来自海豹肢症与躯体失认症等方面的病例,证实部分身体畸形与脑损伤患者的身体表征存在分离;来自橡胶手错觉与全身错觉的实验证据,验证了健康个体身体表征分离的事实。基于上述证据,以身体图式和身体意象为二分维度的模型解释了身体表征的分离。未来的研究可以从神经心理学实验和虚拟现实技术着手,对身体表征的分离进行深入探究。     

Raising the bar on the body beautiful: An analysis of the body image concerns of homosexual men

Research suggests that gay men are at particular risk for body image dissatisfaction. This study seeks to extend research on gay men's body image concerns. A survey assessed the nature and correlates of body image dissatisfaction among 64 gay men. The survey included assessments related to involvement in and perceived acceptance within the gay community, social comparison tendencies, body image satisfaction, self-esteem, and depression. The results indicate that most participants were concerned with muscularity rather than weight. Greater social comparison tendencies and higher body mass index (BMI) were associated with greater body dissatisfaction. Although involvement and perceived acceptance in the gay community did not independently predict general body image dissatisfaction, there is evidence to suggest that the association between body image and self-esteem may be moderated by integration into the gay community, defined as involvement and perceived acceptance. Implications for the further study of gay men's body image are discussed.     

Segmenting the body into parts: Evidence from biases in tactile perception

How do we individuate body parts? Here, we investigated the effect of body segmentation between hand and arm in tactile and visual perception. In a first experiment, we showed that two tactile stimuli felt farther away when they were applied across the wrist than when they were applied within a single body part (palm or forearm), indicating a “category boundary effect”. In the following experiments, we excluded two hypotheses, which attributed tactile segmentation to other, nontactile factors. In Experiment 2, we showed that the boundary effect does not arise from motor cues. The effect was reduced during a motor task involving flexion and extension movements of the wrist joint. Action brings body parts together into functional units, instead of pulling them apart. In Experiments 3 and 4, we showed that the effect does not arise from perceptual cues of visual discontinuities. We did not find any segmentation effect for the visual percept of the body in Experiment 3, nor for a neutral shape in Experiment 4. We suggest that the mental representation of the body is structured in categorical body parts delineated by joints, and that this categorical representation modulates tactile spatial perception.     

Characteristics and effectiveness of stand-alone body image treatments: a review of the empirical literature

This literature review examined the characteristics and effectiveness of treatments dedicated exclusively to body image. A total of 18 studies met selection criteria. All but one involved at least one cognitive-behavioural therapy (CBT) condition and only three compared CBT to another treatment approach. Twelve studies were conducted with non-clinical, body dissatisfied, participants and only one focussed on eating disordered women. Overall, the interventions were highly effective in improving body image and psychological variables and, to a lesser extent, eating attitude and behaviour. Changes were generally maintained at follow-up. Given their efficacy, more controlled trials of stand-alone body image treatments in clinical populations are needed. Investigating approaches other than CBT may open fruitful avenues of body image treatment.     

Implicit body representations and the conscious body image

Recent studies have revealed that somatosensory processing relies on a class of implicit body representations showing large distortions of size and shape. The relation between these representations and the conscious body image remains unclear. Dissociations have been reported in the clinical literature on eating disorders between different body image measures, with larger and more consistent distortions found with depictive measures, in which participants compare their body to a visual depiction of a body, than metric measures, in which participants compare their body to some non-body standard. Here, we compared implicit body representations underlying position sense to the body image measured with both depictive and metric methods. The body image was measured using both a depictive method (template matching) in which participants judged whether their hand was wider or more slender than a shown hand picture, and a metric method (line length) in which participants judged whether different parts of their hand were shorter or longer than a presented line. Consistent with previous findings, characteristic distortions were found for the implicit body representation underlying position sense. These distortions were also found in attenuated form for metric - but not depictive - body image measures. While replicating the basic dissociation between implicit body representations and the conscious body image, these results demonstrate that this dissociation is not absolute and specific tasks may utilise both to varying degrees depending on task demands. Metric measures may not be pure measures of body image, but some combination of visual and somatosensory body representations.     

The relative contributions of subjective and objective measures of body shape and size to body image and disordered eating in women

This research explored the relative contributions of subjective perceptions of body weight and body shape/proportion, as well as objective measures of body mass index (BMI) and waist-to-hip ratio (WHR) to disordered eating, exercise involvement, and body image. One hundred and fifty-eight female university students completed questionnaires and provided body measurements for this study. Although an interaction between BMI and WHR was found for some measures (i.e., Eating Disorder Examination Questionnaire total and subscale scores), results indicated that BMI was consistently the better objective predictor of disordered eating and body image. Subjective perceptions of body weight and, to a lesser extent, body shape, were found to account for the greatest proportion of variance in the dependent measures (disordered eating, body esteem, and body dissatisfaction). Overall, these results offer more support for sociocultural theories emphasizing the importance of thinness for women, than evolutionary theories emphasizing the role of WHR.     

My body until proven otherwise: Exploring the time course of the full body illusion

Evidence from the Full Body Illusion (FBI) has shown that adults can embody full bodies which are not their own when they move synchronously with their own body or are viewed from a first-person perspective. However, there is currently no consensus regarding the time course of the illusion. Here, for the first time, we examined the effect of visuomotor synchrony (synchronous/asynchronous/no movement) on the FBI over time. Surprisingly, we found evidence of embodiment over a virtual body after five seconds in all conditions. Embodiment decreased with increased exposure to asynchronous movement, but remained high in synchronous and no movement conditions. We suggest that embodiment of a body seen from a first-person perspective is felt by default, and that embodiment can then be lost in the face of contradictory cues. These results have significant implications for our understanding of how multisensory cues contribute to embodiment.     

Self-schema and social comparison explanations of body dissatisfaction: a laboratory investigation

The current study was an investigation of the self-schema and social comparison theories of body dissatisfaction. The social comparison manipulation consisted of exposure to one of three levels of comparison figure: upward, downward, or no comparison. Two different imagery exercises served to prime either a participants’ appearance self-schema, or a non-appearance schema. Participants completed state measures of body image and mood at pre- and posttest. Results indicated no significant interaction between priming and social comparison and no significant main effect for priming. However, there was a significant effect of social comparison, such that those in the downward comparison condition showed an increase in body satisfaction and positive mood. Results are discussed in the context of self-schema theory and social comparison, and suggestions are given for future research that might further shed light on these theoretical approaches for understanding body dissatisfaction.     

Hair today, gone tomorrow: a comparison of body hair removal practices in gay and heterosexual men

Although hairlessness is rapidly becoming a component of the ideal male body, little research has examined men's concerns about their body hair or their hair removal practices. Samples of gay and heterosexual men completed questionnaires that assessed whether they had ever removed their back, buttock or pubic hair, the frequency with which they did so, the methods used and their self-reported reasons for removing this hair, as well as their level of appearance investment. Results indicated that many gay and heterosexual men remove their back, buttock and pubic hair regularly and that their primary reason for doing so is to maintain or improve their appearance. The frequency of hair removal was also associated with the motivational salience component of appearance investment. The findings offer further support to the premise that gay and heterosexual men exhibit similar body image concerns.     

Self-compassion moderates the relationship between body mass index and both eating disorder pathology and body image flexibility

The current study examined whether self-compassion, the tendency to treat oneself kindly during distress and disappointments, would attenuate the positive relationship between body mass index (BMI) and eating disorder pathology, and the negative relationship between BMI and body image flexibility. One-hundred and fifty-three female undergraduate students completed measures of self-compassion, self-esteem, eating disorder pathology, and body image flexibility, which refers to one's acceptance of negative body image experiences. Controlling for self-esteem, hierarchical regressions revealed that self-compassion moderated the relationships between BMI and the criteria. Specifically, the positive relationship between BMI and eating disorder pathology and the negative relationship between BMI and body image flexibility were weaker the higher women's levels of self-compassion. Among young women, self-compassion may help to protect against the greater eating disturbances that coincide with a higher BMI, and may facilitate the positive body image experiences that tend to be lower the higher one's BMI.     

The effects of exposure to feminist ideology on women's body image

Body image disturbance has become a common problem among women and there is a need to focus on creating empirically supported treatments. Psychoeducational interventions have reduced body image dissatisfaction, but their impact is limited because they do not offer women adaptive methods of interpreting the many appearance-related messages they receive. This study examined if exposure to a feminist perspective may provide alternative interpretations of cultural messages, thereby increasing body image satisfaction. Participants were randomly assigned to a feminist or psychoeducational intervention, or a control group. Exposure to the feminist condition resulted in increased self-identification as a feminist and greater appearance satisfaction, and changes in feminist identity were related to positive changes in body image. The findings indicate that exposure to feminist theories may serve as an effective intervention strategy.     

Avatar body dimensions and men's body image

Two online surveys examined the significance of the visual analogues, or ‘avatars’, men (total N = 266) create and use online. Two-dimensional (adiposity × muscle) somatomorphic matrices revealed that avatars are generally thinner than their creator's actual body and similar to their ideal, but more muscular than either their actual or ideal. Men's ratings of the importance of their avatar's appearance correlated with their actual weight and muscle concerns, and disparity between their avatar and actual body dimensions predicted their offline context body change concerns additional to that accounted for by disparity between their ideal and actual bodies. Together with the observation that men also reported higher self-esteem, less social interaction anxiety and less social phobia while online (which correlated with the time they spent online), these results suggest that the physical dimensions of avatars used in social interactions online may serve a compensatory function.