Body Integrity Identity Disorder: From A Psychological to A Neurological Syndrome

Body Integrity Identity Disorder (BIID) is a condition in which individuals experience an intense desire for amputation of an healthy limb. Recently, McGeoch and colleagues provided the first direct evidence that this syndrome may be neurological rather than psychological in its origin. However, before including BIID in body ownership disorders, several concerns should be clarified, exploring other components of body representation and not only somatosensory perception.     

Body Integrity Identity Disorder: Deranged Body Processing,Right Fronto-Parietal Dysfunction,and Phenomenological Experience of Body Incongruity

Body integrity identity disorder (BIID) is characterised by profound experience of incongruity between the biological and desired body structure. The condition manifests in “non-belonging” of body parts, and the subsequent desire to amputate, paralyse or disable a limb. Little is known about BIID; however, a neuropsychological model implicating right fronto-parietal and insular networks is emerging, with potential disruption to body representation. We argue that, as there is scant systematic research on BIID published to date and much of the research is methodologically weak, it is premature to assume that the only process underlying bodily experience that is compromised is body representation. The present review systematically investigates which aspects of neurological processing of the body, and sense of self, may be compromised in BIID. We argue that the disorder most likely reflects dysregulation in multiple levels of body processing. That is, the disunity between self and the body could arguably come about through congenital and/or developmental disruption of body representations, which, together with altered multisensory integration, may preclude the experience of self-attribution and embodiment of affected body parts. Ulimately, there is a need for official diagnostic criteria to facilitate epidemiological characterisation of BIID, and for further research to systematically investigate which aspects of body representation and processing are truly compromised in the disorder.     

Amputees by choice: body integrity identity disorder and the ethics of amputation

ABSTRACT Should surgeons be permitted to amputate healthy limbs if patients request such operations? We argue that if such patients are experiencing significant distress as a consequence of the rare psychological disorder named Body Integrity Identity Disorder (BIID), such operations might be permissible. We examine rival accounts of the origins of the desire for healthy limb amputations and argue that none are as plausible as the BIID hypothesis. We then turn to the moral arguments against such operations, and argue that on the evidence available, none is compelling. BIID sufferers meet reasonable standards for rationality and autonomy: so as long as no other effective treatment for their disorder is available, surgeons ought to be allowed to accede to their requests.     

Types of body representation and the sense of embodiment

The sense of embodiment is vital for self recognition. An examination of anosognosia for hemiplegia—the inability to recognise that one is paralysed down one side of one’s body—suggests the existence of ‘online’ and ‘offline’ representations of the body. Online representations of the body are representations of the body as it is currently, are newly constructed moment by moment and are directly “plugged into” current perception of the body. In contrast, offline representations of the body are representations of what the body is usually like, are relatively stable and are constructed from online representations. This distinction is supported by an analysis of phantom limb—the feeling that an amputated limb is still present—phenomena. Initially it seems that the sense of embodiment may arise from either of these types of representation; however, an integrated representation of the body seems to be required. It is suggested information from vision and emotions is involved in generating these representations. A lack of access to online representations of the body does not necessarily lead to a loss in the sense of embodiment. An integrated offline representation of the body could account for the sense of embodiment and perform the functions attributed to this sense.     

Facial asymmetry detection in patients with body dysmorphic disorder

Cognitive-behavioral models of body dysmorphic disorder (BDD) propose that individuals with BDD may possess a better or more developed sense of aestheticality than do individuals without BDD. Evidence for this proposition, however, is limited. One perceptual process that could contribute to heightened aestheticality is the ability to detect differences in symmetry. In this experiment we tested whether individuals with BDD (n = 20), relative to individuals with obsessive compulsive disorder (OCD; n = 20) and healthy controls (n = 20), show an enhanced ability to detect differences in the symmetry of others’ faces, symmetry of dot arrays, and/or show a greater preference for symmetrical faces. Individuals with BDD were not significantly more accurate in detecting differences in facial symmetry or dot arrays relative to individuals with OCD and healthy controls. Individuals with OCD took longer to make facial symmetry judgments than did individuals in the other two groups. All participants, regardless of diagnostic group, preferred more symmetrical faces than nonsymmetrical ones. Taken together, our results do not support a heightened perceptual ability or evaluative preference for symmetry among individuals with BDD.     

Morality Work among the Transabled

In the present article, I address the process of moral stigma resistance using an accounts studies framework. Specifically, I delineate and illustrate the concept of morality work. I demonstrate morality work empirically through a qualitative analysis of 17 years (1994–2011) of blog posts, archived content, and links to and from Transabled.org. Transabled.org is a website, blog, support group, and interaction forum for people with body integrity identity disorder (BIID)—a highly stigmatizing condition of incorrectly abled embodiment. Detractors accuse people with BIID of deep moral failings, including sexual perversion, dishonesty, greed, and attention seeking. In turn, persons with BIID neutralize claims of immorality through medicalization and biologization, and locate themselves on a moral high ground with a discourse of authenticity. In deconstructing transabled bloggers’ moral battle, I examine the process underlying deviant accounts.     

Categorical perception of tactile distance

The tactile surface forms a continuous sheet covering the body. And yet, the perceived distance between two touches varies across stimulation sites. Perceived tactile distance is larger when stimuli cross over the wrist, compared to when both fall on either the hand or the forearm. This effect could reflect a categorical distortion of tactile space across body-part boundaries (in which stimuli crossing the wrist boundary are perceptually elongated) or may simply reflect a localised increased in acuity surrounding anatomical landmarks (in which stimuli near the wrist are perceptually elongated). We tested these two interpretations across two experiments, by comparing a well-documented bias to perceive mediolateral tactile distances across the forearm/hand as larger than proximodistal ones along the forearm/hand at three different sites (hand, wrist, and forearm). According to the ‘categorical’ interpretation, tactile distances should be elongated selectively in the proximodistal axis thus reducing the anisotropy. According to the ‘localised acuity’ interpretation, distances will be perceptually elongated in the vicinity of the wrist regardless of orientation, leading to increased overall size without affecting anisotropy. Consistent with the categorical account, we found a reduction in the magnitude of anisotropy at the wrist, with no evidence of a corresponding localised increase in precision. These findings demonstrate that we reference touch to a representation of the body that is categorically segmented into discrete parts, which consequently influences the perception of tactile distance.     

Body-size stigmatization by preschool girls: In a doll's world,it is good to be “Barbie”

A number of studies have measured body size stigmatization, that is, the assigning of negative characteristics to individuals who are considered fat, in samples of children as young as preschool-age. The results of such studies are fairly consistent, but may be criticized for the abstract nature of the line drawings typically used as test stimuli. In the present study the utility of using toy dolls to gauge young girls’ views toward different body shapes was assessed. Forty girls ages 3½–5½ were asked to assign various traits to one of three dolls (thin, average, and fat). As with previous work, responses fell out in a stereotypical pattern, with the positive characteristics attributed most often to the thin or average doll and all of the negative characteristics most often to the fat doll. The strengths and weaknesses of this doll paradigm in studies of body-size stigmatization by young children are discussed.     

Mental body distance comparison: A tool for assessing clinical disturbances in visual body image

Despite numerous body size estimation studies, it cannot be concluded that the disturbance of body image in anorexia nervosa (AN) is specifically one of the visual body images.We adopted a visual imagery method, the Distance Comparison task, to enable across-population testing of differences in visual body image with respect to shape. Participants were asked to mentally scan across two body widths (e.g. hips and shoulders) and to decide as quickly as possible which one was longer or shorter. If the mental representation accessed to make such comparisons is visual, an inverse relation would be expected between RT and distance difference on the body to be judged (i.e. actual difference in size between the two body widths), with accuracy increasing with increasing distance difference. Females with high body shape concern (scoring high on the Body Shape Questionnaire: BSQ, n = 23) were compared to females with low body shape concern (scoring low on the BSQ, n = 19).RT and distance differences on the body demonstrated standard distance differences effects: RT increased and accuracy decreased with decreasing distance differences on the body. Groups differed with respect to accuracy, in that females high on body shape concern were significantly less accurate than females low on body shape concern when making evaluations involving small (?9 cm) differences, which implies a less appropriate visual image of the own body in the former group. With respect to the relation between RT and body distance difference, on the other hand, there were no differences between groups. We concluded that evaluations of own body size employ visual imagery and that the distance comparison task holds promise for the assessment of visual disturbances in body image in clinical populations.     

The multisensory basis of the self: From body to identity to others

By grounding the self in the body, experimental psychology has taken the body as the starting point for a science of the self. One fundamental dimension of the bodily self is the sense of body ownership that refers to the special perceptual status of one’s own body, the feeling that “my body” belongs to me. The primary aim of this review article is to highlight recent advances in the study of body ownership and our understanding of the underlying neurocognitive processes in three ways. I first consider how the sense of body ownership has been investigated and elucidated in the context of multisensory integration. Beyond exteroception, recent studies have considered how this exteroceptively driven sense of body ownership can be linked to the other side of embodiment, that of the unobservable, yet felt, interoceptive body, suggesting that these two sides of embodiment interact to provide a unifying bodily self. Lastly, the multisensorial understanding of the self has been shown to have implications for our understanding of social relationships, especially in the context of self–other boundaries. Taken together, these three research strands motivate a unified model of the self inspired by current predictive coding models.     

Experiential avoidance in body dysmorphic disorder

Experiential avoidance (i.e., the attempt to avoid certain internal experiences including bodily sensations, thoughts, emotions, memories, and urges) has been studied in various psychological disorders. However, research examining experiential avoidance in individuals with body dysmorphic disorder (BDD) is limited and inconsistent. The present study compared experiential avoidance in individuals with primary BDD (n = 23) to healthy controls (n = 22). Standardized measures were used to assess baseline clinical characteristics as well as experiential avoidance. Compared to healthy controls, individuals with BDD presented with significantly greater experiential avoidance (p < .001, d = −2.51). In BDD, experiential avoidance was positively correlated with depressive symptoms (p < .01) and avoidant coping strategies (p < .01). Clinician sensitivity to experiential avoidance may serve to improve the course of treatment for BDD.     

Body image distortions in healthy adults

Distortions of body image have often been investigated in clinical disorders. Much of this literature implicitly assumes healthy adults maintain an accurate body image. We recently developed a novel, implicit, and quantitative measure of body image — the Body Image Task (BIT). Here, we report a large-scale analysis of performance on this task by healthy adults. In both an in-person and an online version of the BIT, participants were presented with an image of a head as an anchoring stimulus on a computer screen, and told to imagine that the head was part of a mirror image of themselves in a standing position. They were then instructed to judge where, relative to the head, each of several parts of their body would be located. The relative positions of each landmark can be used to construct an implicit perceptual map of bodily structure. We could thus measure the internally-stored body image, although we cannot exclude contributions from other representations. Our results show several distortions of body image. First, we found a large and systematic over-estimation of width relative to height. These distortions were similar for both males and females, and did not closely track the idiosyncrasies of individual participant's own bodies. Comparisons of individual body parts showed that participants overestimated the width of their shoulders and the length of their upper arms, relative to their height, while underestimating the lengths of their lower arms and legs. Principal components analysis showed a clear spatial structure to the distortions, suggesting spatial organisation and segmentation of the body image into upper and lower limb components that are bilaterally integrated. These results provide new insight into the body image of healthy adults, and have implications for the study and rehabilitation of clinical populations.     

Higher inhibitory control is required to escape the innate attraction to effort minimization

Recent evidence suggests humans have an automatic attraction to effort minimization. Yet, how this attraction is associated with response inhibition is still unclear. Here, we used go/no-go tasks to capture inhibitory control in response to stimuli depicting physical activity versus physical inactivity in 59 healthy young individuals. Higher commission errors (i.e., failure to refrain a response to a “no-go” stimulus) indicated lower inhibitory control. Based on the energetic cost minimization theory, we hypothesized that participants would exhibit higher commission errors when responding to physical inactivity stimuli rather than physical activity stimuli. Mixed effects models showed that, compared to physical activity stimuli, participants exhibited higher commission errors when responding to stimuli depicting physical inactivity (odds ratio = 1.59, 95% Confidence Interval = 1.18 to 2.16, p = .003). These results suggest that physical inactivity stimuli might require high response inhibition. This study lends support for the hypothesis that an attraction to effort minimization might affect inhibitory processes in the presence of stimuli related to this minimization. The study pre-registration form can be found at https://doi.org/10.17605/OSF.IO/RKYHB.     

Does the body talk to the body? The relationship between different body representations while observing others’ body parts

The way human bodies are represented is central in everyday activities. The cognitive system must combine internal, visceral, and somatosensory, signals to external, visually driven information generated from the spatial placement of others’ bodies and the own body in the space. However, how different body representations covertly interact among them when observing human body parts is still unclear. Therefore, we investigated the implicit processing of body parts by manipulating either the body part stimuli’ posture (conditions a and b) or the participants’ response body posture (conditions c, d, and e) in healthy participants (N = 70) using a spatial compatibility task called Sidedness task. The task requires participants to judge the colour of a circle superimposed on a task-irrelevant body part picture. Responses are facilitated when the spatial side of the responding hand corresponds to the spatial code generated by the hand stimulus's position with respect to a body of reference. Results showed that the observation of the task-irrelevant body parts oriented participants’ attention and facilitated responses that were spatial compatible with the spatial position such body parts have within a configural representation of the body structure (i.e., Body Structural Representation) in all the five experimental conditions. Notably, the body part stimuli were mentally attached to the body according to the most comfortable and less awkward postures, following the anatomo-physiological constraints. Moreover, the pattern of the results was not influenced by manipulating the participants’ response postures, suggesting that the automatic and implicit coding of the body part stimuli does not rely on proprioceptive information about one's body (i.e., Body Schema). We propose that the human body's morphometry knowledge is enriched by biomechanical and anatomo-physiological information about the real body movement possibilities. Moreover, we discuss the importance of the automatic orienting of attention based on the sidedness within the context of imitational learning.     

The effects of fat talk on body dissatisfaction and eating behavior: The moderating role of dietary restraint

Although research suggests that fat talk, the normalized conversations that involve degrading one's body shape/weight and size, can increase body dissatisfaction and disordered eating behavior, the extent to which dietary restraint may moderate these relationships remains uncertain. A pilot study (N = 30) comparing online videos with researcher-developed vignettes as prospective manipulations for fat talk exposure suggested use of the vignettes as potent yet subtle stimuli. In the main study, women undergraduates (N = 116) were randomized to read a fat talk or neutral vignette and then completed standardized measures of body dissatisfaction and dietary restraint while being concurrently presented with food stimuli. Results suggest significant moderation effects for dietary restraint: whereas fat talk exposure was associated with increased body dissatisfaction among low dietary restrainers, it appeared to reduce food consumption among high dietary restrainers. Findings highlight the importance of individual differences in shaping responses to fat talk.     

Evidence from the eyes: Threatening postures hold attention

Efficient detection of threat provides obvious survival advantages and has resulted in a fast and accurate threat-detection system. Although beneficial under normal circumstances, this system may become hypersensitive and cause threat-processing abnormalities. Past research has shown that anxious individuals have difficulty disengaging attention from threatening faces, but it is unknown whether other forms of threatening social stimuli also influence attentional orienting. Much like faces, human body postures are salient social stimuli, because they are informative of one’s emotional state and next likely action. Additionally, postures can convey such information in situations in which another’s facial expression is not easily visible. Here we investigated whether there is a threat-specific effect for high-anxious individuals, by measuring the time that it takes the eyes to leave the attended stimulus, a task-irrelevant body posture. The results showed that relative to nonthreating postures, threat-related postures hold attention in anxious individuals, providing further evidence of an anxiety-related attentional bias for threatening information. This is the first study to demonstrate that attentional disengagement from threatening postures is affected by emotional valence in those reporting anxiety.     

The harmful and beneficial impacts of weight bias on well-being: the moderating influence of weight status

Weight bias is evident among normal weight and obese individuals. This weight bias may be associated with comparisons to others, which may enhance feelings of self-worth. However, the ego-enhancing versus ego-diminishing influence of these evaluations may be moderated by the individual's weight status, and the strength of these effects may be moderated by gender. Eight-five participants completed the Implicit Associations Test, questionnaires assessing explicit weight bias, body image, and self-esteem, and height and weight assessments. Implicit weight bias was prevalent among all individuals, p < .001, and was associated with a more positive body image, ps < .05, and higher self-esteem, ps < .01, for thinner individuals but a more negative body image and lower self-esteem for heavier individuals. Gender moderation effects were not observed. It is arguably problematic that the positive benefits to normal weight individuals’ self-esteem and body image appear to come via negative comparisons with overweight individuals.     

Emotion context insensitivity in major depressive disorder

The present study tested 3 competing views of how depression alters emotional reactivity: positive attenuation (reduced positive), negative potentiation (increased negative), and emotion context insensitivity (ECI; reduced positive and negative). Normative and idiographic stimuli that elicited happy, sad, and neutral states were presented to currently depressed, formerly depressed, and healthy control individuals while experiential, behavioral, and autonomic responses were measured. Currently depressed individuals reported less sadness reactivity and less happiness experience across all conditions than did the other participants, and they exhibited a more dysphoric response to idiographic than to normative stimuli. Overall, data provide partial support for the positive attenuation and ECI views. Depression may produce mood-state-dependent changes in emotional reactivity that are most pronounced in emotion experience reports.