Beyond differences between the body schema and the body image: insights from body hallucinations

The distinction between the body schema and the body image has become the stock in trade of much recent work in cognitive neuroscience and philosophy. Yet little is known about the interactions between these two types of body representations. We need to account not only for their dissociations in rare cases, but also for their convergence most of the time. Indeed in our everyday life the body we perceive does not conflict with the body we act with. Are the body image and the body schema then somehow reshaping each other or are they relatively independent and do they only happen to be congruent? On the basis of the study of bodily hallucinations, we consider which model can best account for the body schema/body image interactions.     

Suicide schema in schizophrenia: the effect of emotional reactivity, negative symptoms and schema elaboration

Suicide risk is thought to increase with a greater potential for activation of suicide-related schemas. Suicide schemas are less likely to be activated with reductions of emotional range associated with certain negative symptoms of schizophrenia. The study tested whether suicide risk would increase in patients with recent onset schizophrenia with increased potential for suicide schema activation as indicated by lower levels of specific negative symptoms that reflected emotional reactivity, namely emotional withdrawal and blunted affect. A logistic regression analysis of baseline data of 278 recent onset schizophrenic patients with a measure of suicide behaviour as the dependent variable and negative symptoms, delusions, hallucinations, depression, gender, episode, ethnicity, education, age, duration of untreated psychosis and substance use as independent variables was carried out. Emotional withdrawal, but not blunted affect was significant and negatively associated, and depression positively associated with suicide behaviour. There was evidence to indicate that restricted emotions are associated with reduced suicide risk as predicted.     

The role of the dynamic body schema in praxis: evidence from primary progressive apraxia

On an influential model of limb praxis, ideomotor apraxia results from damage to stored gesture representations or disconnection of representations from sensory input or motor output (Heilman & Gonzalez Rothi, 1993; Gonzalez Rothi et al., 1991). We report data from a patient with progressive ideomotor limb apraxia which cannot be readily accommodated by this model. The patient, BG, is profoundly impaired in gesturing to command, to sight of object, and to imitation, but gestures nearly normally with tool in hand and recognizes gestures relatively well. In addition, performance is profoundly impaired on imitation of meaningless gestures and on tasks requiring spatiomotor transformations of body-position information. We provide evidence that BG's apraxia is largely attributable to impairments external to the stored gesture system in procedures coding the dynamic positions of the body parts of self and others; that is, the body schema. We propose a model of a dynamic, interactive praxis system subserved by posterior parietal cortex in which stored representational elements, when present, provide "top-down" support to spatiomotor procedures computed on-line. In addition to accounting for BG's performance, this model accommodates a common pattern of ideomotor apraxia more readily than competing accounts.     

Multiple timescales of body schema reorganization due to plastic surgery

Plastic surgery modifies the distribution of mass centers of a person’s body segments, changing his or her posture. The functional reorganization processes that lead subjects to re-integrate these body changes into a new stable body (posture) schema is poorly understood but current theories suggest the possible contribution of two components: a feedback mechanism that strongly depends on sensory input and an internal model that is relatively less dependent on sensory input and improves posture control, for example by compensating for delayed feedback. To assess the relative contributions of these two mechanisms during the functional reorganization of a posture scheme, we have conducted a longitudinal postural study in a population of healthy adults who were subject to breast plastic surgery to reduce or augment body weight. We measured participants’ orthostatic posture and ground reaction force immediately after, after 4 months, and 1 year after the surgery. To investigate the role of visual sensory information in the reorganization process we tested the participants with eyes open and closed. Our results indicate that participants find a new dynamical equilibrium within a few days. However, posture maintenance remains sub-optimal long after the center of masses and the resultant of ground reaction force stop changing; in some cases, for more than 4 months. Furthermore, the re-adaptation process is faster and more efficient in the eyes-open than in the eyes-closed condition. These results suggest that the reorganization involves different subsystems (responsible for the biomechanical changes, the re-calibration of feedback mechanisms, and the re-adaptation of internal models), which act at different timescales.     

Coping with body image changes following a disfiguring burn injury.

The influence of emotion-focused coping on distress following disfiguring injury was examined. Two types of emotion-focused coping (i.e., venting emotions vs. mental disengagement) were assessed in 78 patients with burn injury at baseline during acute hospitalization. Body image dissatisfaction (BID) was assessed 1 week and 2 months following discharge. Use at baseline of both venting emotions and mental disengagement, compared with use of only one or neither of these coping methods, was associated at the 2-month postdischarge follow-up with significantly higher BID related to nonfacial aspects of appearance and with a greater negative social impact of disfigurement. D. M. Wegner's (1994) theoretical model of mental control and a proposed motivational analysis are used to interpret these findings.     

Measurement of body image satisfaction using computer manipulation of a digital image

The authors investigated a method for assessing body image satisfaction based on computer manipulation of a digitized image of self using a sample of 56 female students aged 17 to 22 years. The total percentage change when re-sizing the actual image to the ideal by the computer adjustment method was significantly correlated with the figural/silhouette discrepancy method. Both of these measures were correlated significantly with body part satisfaction and body mass index but not with social physique anxiety. Although for this sample the 2 methods yielded similar results, the computer adjustment method addresses several limitations of the figural/silhouette method, such as scale coarseness and the accuracy of proportional change between figural/silhouettes. Furthermore, by using the individual's actual image, potential confounds associated with stylized figure drawings that are typically based on Caucasian physical features are removed. Finally, this method also takes into account the importance of various body parts for determining body image satisfaction.     

Impact of a healthy body image program among adolescent boys on body image,negative affect,and body change strategies

This study evaluated the effectiveness of a healthy body image program. In total, 421 adolescent boys completed a five-session intervention program or a wait list control group. There were no differences between the intervention and the control group at post-intervention or any of the follow-up times. Boys in the intervention group who were one standard deviation above the mean on body dissatisfaction at baseline, demonstrated a reduction in negative affect in the intervention group at post-test and 6 months follow-up. Prevention programs need to target boys who are at risk of adopting health risk behaviors, rather than being universally applied.     

Psychic tonus, body schema and the parietal lobes: a multiple lesion case analysis

The psychic tonus model (Braun and colleagues, 1999, 2002, 2003, 2006) states that the left hemisphere is a "booster" of internal experience and behavior in general, and that the right hemisphere is a "dampener". Twenty-five patients with a "positive" extreme disturbance of body schema (somatoparaphrenia) and 37 patients with a "negative" disturbance of body schema (autotopagnosia or Gerstmann's syndrome), all following a unilateral parietal lesion, were found in the literature and were analyzed to test predictions from Braun's "psychic tonus" model. As expected, patients with a positive syndrome had a right hemisphere lesion significantly more frequently, and those with a negative syndrome had a left hemisphere lesion significantly more frequently. Thus the psychic tonus model of hemispheric specialization, previously supported with regard to psychomotor baseline, libido, talkativeness, memory, auditory and visual perceptual tonus, now incorporates the tonus of representation of the body (body schema) in the parietal lobes.     

Development of internal body image from childhood to early adolescence

The study aimed at providing a psychogenetic characterization of the developmental patterns through which the graphic representations of the inside of the body progress, and at testing the developmental hypothesis of a progressive integration of genital parts into the internal body image. The drawings of the inside of the body by 360 children of both sexes and of age 5 to 10 yr., and by 213 early adolescents, boys and girls of ages 11 to 14 yr., were analyzed on the basis of a series of qualitative and quantitative criteria. The relationship between age and type of drawing corresponds to expectations in children and appears less linear for early adolescents. Further, data support the developmental process of integration of genitals into the body image and show differential aspects in boys and girls.     

New assessments of weight-related body image derived from extant instruments

A study of 79 female college students examined the reliability and validity of two new size/weight-related measures of body image. The Body-size Appraisal Scale and the Overweight Preoccupation Scale were derived from existing instruments. Analyses supported the internal consistency and 2-wk. test-retest reliability of both new scales. Correlations of scores on each scale with measures of anxiety about being fat, negative body-image affect and avoidance, restrained and bulimic eating, and depression support their concurrent and construct validity. Scores on the Overweight Preoccupation Scale were also related to the extent of investment in physical appearance. Regression analyses indicated that each new scale could be predicted from several other conceptually relevant body-image attitudes, even after actual body weight was controlled.     

The body schema and multisensory representation(s) of peripersonal space

To guide the movement of the body through space, the brain must constantly monitor the position and movement of the body in relation to nearby objects. The effective piloting of the body to avoid or manipulate objects in pursuit of behavioural goals requires an integrated neural representation of the body (the body schema) and of the space around the body (peripersonal space). In the review that follows, we describe and evaluate recent results from neurophysiology, neuropsychology, and psychophysics in both human and non-human primates that support the existence of an integrated representation of visual, somatosensory, and auditory peripersonal space. Such a representation involves primarily visual, somatosensory, and proprioceptive modalities, operates in body-part-centred reference frames, and demonstrates significant plasticity. Recent research shows that the use of tools, the viewing of ones body or body parts in mirrors, and in video monitors, may also modulate the visuotactile representation of peripersonal space.

Improving body image one step at a time: greater pedometer step counts produce greater body image improvements

This randomized controlled trial examined whether the number of steps walked during an 11-week action planning intervention would mediate changes in sedentary women's body image. Seventy-five healthy, sedentary women were randomly assigned to either a control group, where they were required to self-monitor their daily pedometer-determined step count, or to an experimental group, where they were asked to self-monitor and form specific action plans for walking. Of the 75 participants randomized, 41 were included in the efficacy analyses. Measured outcomes were satisfaction with physical functioning and physical appearance, and daily pedometer-determined step counts. Greater satisfaction with physical functioning and higher step counts were found for the experimental group. Moreover, the total number of steps walked over Weeks 2-11 was shown to partially mediate the effect of the intervention on satisfaction with physical functioning. These findings suggest that walking greater distances is associated with greater improvement in at least one aspect of women's body images.     

Assessing the importance of letter pairs in initial, exterior, and interior positions in reading

Exterior letter pairs (e.g., d--k in dark) play a major role in single-word recognition, but other research (D. Briihl & A. W. Inhoff, 1995) indicates no such role in reading text. This issue was examined by visually degrading letter pairs in three positions in words (initial, exterior, and interior) in text. Each degradation slowed reading rate compared with an undegraded control. However, whereas degrading initial and interior pairs slowed reading rate to a similar extent, degrading exterior pairs slowed reading rate most of all. Moreover, these effects were obtained when letter identities across pair positions varied naturally and when they were matched. The findings suggest that exterior letter pairs play a preferential role in reading, and candidates for this role are discussed.     

Human figure drawing size and body image in preschool children from a self-physique perspective

To learn about the relationship between size of human figure drawings and the physiques of children, we investigated body image characteristics in childhood by using the Human Figure Drawing test. Height, weight, Kaup Index (a body mass index for children) and Human Figure Drawing traits (vertical height, horizontal width, waist size, surface area of head, surface area of the self-drawing) were measured for drawings of 122 4- to 6-yr.-old children (62 boys, 60 girls). Analysis showed that boys, who are physically larger than girls, produced self-drawings with somewhat larger surface areas. For vertical height of self-drawings of boys, 4-yr.-olds characteristically made taller self-drawings than 5-yr.-olds. While we hypothesized that taller children would make vertically taller self-drawings, we observed a negative relationship between children's physical height and the vertical height of the self-drawings. 4-yr.-old boys showed the most interest in their own physical height, making taller drawings and in doing so gave a clue to an early childhood feature of body image.     

Further tests of Schmidt's schema theory: development of a schema rule for a coincident timing task

The present study investigated the generalizability of Schmidt's (1975) schema theory to an open-skill (Poulton, 1957) situation. Subjects attempted to time a preferred-hand button press so that it was coincident with the lighting of the last of a series of run way lights whose apparent velocity was 4023 mm/sec. Prior to five trials of performance on the criterion task, subjects received 40 trials in which they either (a) watched (low response requirements) or (b) responded with the nonpreferred hand (high response requirements) to a stimulus moving at (a) a constant (2235, 3129, 4917, or 5812 mm/sec) velocity (low stimulus variability) or (b) different velocities (high stimulus variability) from trial to trial. Subjects receiving high stimulus variability and high response requirements during training had significantly lower absolute error on the criterion task than did those in the other conditions. The results were discussed in terms of the type of practice which facilitates development of a schema rule for coincident-timing situations.