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PubMed2001

Body image and dieting behavior in cystic fibrosis.

OBJECTIVE: To examine the relationship between pulmonary function, nutritional status, body image, and eating attitudes in children with cystic fibrosis (CF) compared with healthy controls. METHOD: Seventy-six children with CF (39 girls) and 153 healthy control children (82 girls) were recruited. All children were between 7 and 12 years of age. After being weighed and measured, participants undertook a structured 1-to-1 interview. Four measures were used to assess body image: body size (perception and satisfaction) were ascertained using the Children's Body Image Scale (CBIS), which uses photographs of children of various body mass index (BMI) representative of the range of BMI percentiles for children 7 to 12 years of age. Body size satisfaction was measured by the response to the questions, "Do you think your body is 1) much too thin, 2) too thin, 3) just right, 4) too fat, and 5) much too fat?" Body weight satisfaction was measured by the question, "Would you like your body to be 1) much thinner, 2) a little bit thinner, 3) stay the same, 4) a little bit fatter, and 5) much fatter?" Global self-esteem was measured using the children's version of the Rosenberg Self-Esteem Scale and Body Esteem Scale using a 24-item scale. Dieting behavior was measured by asking directly about previous weight control behaviors, use of the Dutch Eating Behavior-Restraint Scale (DEBQ-R), and, in children who acknowledged previous dieting behavior, the Children's Eating Attitude Test (ChEAT) was additionally administered. Results. Both girls and boys with CF had significantly reduced BMI percentiles compared with control children. Boys with CF did not have a significantly different BMI compared with girls with CF. There were significant positive correlations between forced expiratory volume in 1 second (FEV(1)) (% of predicted) and BMI percentile in girls (r =.35) and boys (r =.50) with CF. Body image perceptions in boys and girls with CF were examined in relation to the healthy control group using 2 (CF and control groups) by 2 (male and female) analysis of variance. The interaction effect was examined to explore the prediction that girls compared with boys with CF would have greater acceptance of their body shape and less desire to become larger. There were no differences between groups or sex in body esteem. On the CBIS body dissatisfaction score, children with CF were significantly more likely to perceive their ideal body size as a little larger than their current size while control children desired a smaller body size than their current size. CF children had a significantly lower mean score for body size satisfaction (an item assessing perception being too thin) and a significantly higher mean score on body weight satisfaction. There was a significant main effect of gender for only 1 measure, difference between the CBIS body dissatisfaction score, with girls being more likely to nominate a smaller ideal than their current figure. There were no significant interaction effects. Of children with CF and a low BMI (</=10th percentile), 25% of girls and 38% of boys thought they were too thin. Fewer girls (19%) than boys (38%) would have liked to be fatter. The CF group had significantly lower mean scores on the DEBQ-R scale compared with controls. Of the children with CF completing the ChEAT (n = 13), none obtained a score of clinical significance compared with 6 (4%) for controls. To examine predictors of BMI a multiple regression analysis was conducted separately for boys and girls with CF and control boys and girls in which the dependent variable was BMI and the independent variables were FEV(1) (% of predicted) (in CF children only), body esteem, self-esteem, and body dissatisfaction score. In the case of boys with CF, the regression equation was significant (Adjusted R(2) = 0.30). In the case of girls with CF, the regression equation was significant (Adjusted R(2) = 0.25) with body dissatisfaction making a significant independent contribution. For control boys the regression equation was significant (Adjusted R(2) = 0.18). Variables making a significant contribution to the equation were body esteem and body dissatisfaction. Finally, for control girls the regression equation was significant (Adjusted R(2) = 0.13). The only variable to make a significant contribution to the equation was body dissatisfaction. DISCUSSION: Children with CF had very similar body esteem and general self-esteem as controls. A consideration of body image constructs does reveal group differences between perception and satisfaction with body size between groups. Children with CF were more likely to perceive their body size as larger than it actually was and have greater satisfaction with their current body size in contrast to control children. The girls and boys with CF with a higher BMI frequently selected a smaller body size as their ideal. (ABSTRACT TRUNCATED)

Attitude↗
PubMed2002

Dieting frequency among college females: association with disordered eating, body image, and related psychological problems.

OBJECTIVE: To examine associations between dieting frequency and eating disorder behaviors, body satisfaction, and related factors. METHOD: Females (N=345) whose average age and body mass index (BMI) were 20.58 and 21.79, respectively, were grouped into three categories of lifetime dieting frequency (never, 1-5 times, or 6 or more times) and matched on current BMI across categories. RESULT: Positive associations were found between dieting frequency and eating disorder symptoms and related problems such as body dissatisfaction, current body size perception, depression, exercise preoccupation, and feelings of ineffectiveness and insecurity. Dieting frequency was inversely associated with self-esteem, ideal body size, emotional regulation, and impulse control. DISCUSSION: Independent of current BMI, frequency of dieting behaviors is strongly associated with negative emotions and problematic behaviors. As this study is correlational in nature, future longitudinal studies should ascertain the sequence of onset of these experiences.

Adolescent↗
PubMed2001

Body image assessment using body size estimation in recent studies on anorexia nervosa. A brief review.

The concept of body image is thought to consist of two components: body size perception and attitudes towards the body. Correspondingly, two distinct modalities of body image dysfunction seem to be relevant for anorexia nervosa: perceptual body size distortion and cognitive-evaluative dissatisfaction. Consequently, various techniques to assess body image have been developed to assess body image disturbance in eating disorders, particularly anorexia nervosa. This review article compares the numerous methods of assessing body image used in recent studies on anorexia nervosa and discusses the various findings. The findings suggest that body image disturbance is not due to any perceptual deficit, but is based on cognitive-evaluative dissatisfaction. Although overestimation of body size is not a universal symptom in eating disorders, this issue is interesting in terms of prognostic and therapeutic implications. Thus, body size estimation remains a worthwhile approach to assessing body image disturbance in eating disorders. The identification of sensory and non-sensory factors in body image is considered a promising issue for further research.

Anorexia Nervosa↗
PubMed1978

Effect of perspective and slant on perception of apparent size and distance.

An experiement was performed to re-examine the role of linear perspective and floor slant on apparent size and distance scales. Misleading perspective cues did not alter the observers' apparent distance scales but did influence the absolute magnitude of distance judgments; floor slant exerted little influence on apparent distance scales or the absolute magnitude of distance judgments. Neither perspective nor slant manipulation reliably affected apparent size scales or exerted more than a minor influence on the absolute magnitude of size judgments.

Cues↗
PubMed1998

Visual size processing in spatial neglect.

Evidence from the use of the landmark task and from two size-matching tasks shows that many patients with left-sided neglect systematically under-perceive visual extent in leftward parts of space. This perceptual distortion of size serves to explain the occurrence of rightward line-bisection errors in most neglect patients. One possibility is that attentional biases of a chronic nature might underlie these perceptual changes seen in neglect patients. But contrary to this idea, we have found that attentional cueing in the landmark task causes changes in neglect patients exactly opposite to those seen in healthy subjects. The distortions of size perception seen in neglect could instead be caused by a high-level alteration of visual processing rather than by an attentional bias. In order to explore which visual stream of cortical processing might be compromised in such a disorder, we have begun to examine neglect patients on visuomotor as well as perceptual tasks. We have found clear evidence in one patient for intact grip scaling for object size in the neglected half of space, despite gross perceptual underestimations of the same objects. This result suggests that neglect can occur without major disruption of the dorsal stream, and may result instead from damage to a cortical system whose predominant visual input comes from the ventral stream.

Attention↗
PubMed2001

Impaired size processing for single objects after hemispatial neglect.

Some patients with hemispatial neglect show deficits in horizontal size perception. Most previous studies investigating this effect required the relative comparison of two horizontal stimuli. We examined whether the effect would also be present for single stimuli which would reflect an impairment in the computation of absolute horizontal length. Ten neglect patients, five with and five without hemianopia, and two control groups were asked to verbally judge the length of horizontal lines varying in length (3, 3.5, 4 inches) and spatial location (extreme left to extreme right). Three of the ten neglect patients judged a single object on the left as significantly smaller than a single object on the right, thus demonstrating a size processing deficit. This deficit was unrelated to hemianopia.

Aged↗
PubMed1999

Weight-related attitudes and behaviors in fourth grade American Indian children.

OBJECTIVE: American Indian children have a high prevalence of obesity, yet little is known about weight-related attitudes and the prevalence of dieting in this population. This study assessed weight concerns, body size perceptions, weight reduction attempts, and weight loss methods in fourth grade American Indian children. RESEARCH METHODS AND PROCEDURES: Participants (n = 304) attended one of eight schools in the Pathways Feasibility Study. Question and answer choices were read to children by trained staff, and children marked their own answers. RESULTS: Thirty-eight percent of the children reported that they had tried to lose weight. The most common strategy for weight reduction was exercising more. Girls were more likely than boys to be dissatisfied with their body size (48% of girls vs. 34% of boys desired a slimmer body size; 22% of girls vs. 15% of boys desired a larger body size; p<0.001). Children who had tried to lose weight were more likely to indicate that the size they most desired and the most healthy size were smaller than their perceived size (p<0.001). Children who reported trying to lose weight were also more likely to want to be skinnier and to be unhappy about their weight than were children who did not report trying to lose weight (p<0.001 for both). DISCUSSION: We conclude that weight loss attempts and weight-related concerns are prevalent in American Indian children at a young age.

Arizona↗
PubMed2003

Perceptual efficacy of electrical stimulation of human retina with a microelectrode array during short-term surgical trials.

PURPOSE: This work is part of a feasibility assessment of a retinal prosthesis as a means to restore vision to patients with blindness caused by retinitis pigmentosa. The primary goal was to assess the concordance of the form of induced perception and the pattern of electrical stimulation of the retina, and the reproducibility of the responses. METHODS: Five volunteers with severe retinitis pigmentosa and one with normal vision were studied. A companion paper in this issue provides details on demographics, visual function, surgical methods, general stimulation strategy, and data analysis. Volunteers were awake during surgery while a 10-microm-thick, microfabricated electrode array was placed on the retina. The array was connected to extraocular current sources that delivered charges to 50-, 100-, and 400-microm-diameter electrodes. Negative control trials were randomly included. Perceptual quality was judged by the similarity between the form of stimulation and perception (i.e., accuracy) and the reproducibility of responses. RESULTS: Only 1 of 40 control tests yielded a false-positive result. On average, volunteers 3, 5, and 6 reported percepts that matched the stimulation pattern 48% and 32% of the time for single- and multiple-electrode trials, respectively. Two-point discrimination in the best cases may have been achieved in two blind subjects using (center-to-center) electrode separation of 600 and 1960 microm. Reproducibility was achieved 66% of the time in the blind subjects. By comparison, in the normal-sighted subject, perceptual form was reported accurately 57% of the time, with 82% reproducibility, and two-point discrimination may have been achieved in one trial with 620-microm electrode spacing and in two trials each with 1860- and 2480-microm electrode spacing. In subjects 5 and 6, perceptual size was inconsistently related to the charge, although relatively large differences in charge (median: 0.55 microcoulombs [microC]) between two trials produced differently sized percepts. Longer stimuli did not produce rounder percepts. CONCLUSIONS: Single percepts induced by single-electrode stimulation were relatively small, but the form of percepts, especially after multielectrode stimulation, often did not match the stimulation pattern, even in a normal-sighted volunteer. Reproducible percepts were more easily generated than those that matched the stimulation pattern.

Adult↗
PubMed1994

How accurate is size and distance perception for very far terrestrial objects? Function and causality.

This study investigated absolute estimation of size and distance for natural and artificial objects at viewing distances of 1.1-15.3 km (Experiments 1 and 2) and 0.4-5.0 m (Experiment 3). The main results were that, regardless of distance range, size and distance estimates (S' and D') were related to objective size and distance (S and D), respectively, by a power function with an exponent of unity, but great individual differences in exponent were obtained for the far objects. The ratio S'/D' was reasonably represented by S'/D' = K theta n and S'/D' = tan(a theta +b), rather than S'/D' = tan theta, where theta is the visual angle. Partial correlations were obtained to examine whether (1) apparent size is determined by taking apparent distance into account or (2) both apparent size and apparent distance are determined directly by external stimuli. The combined data for the far objects and the data for the close objects showed that there were high correlations between S and S' and between D and D' and a low correlation between D' and S'. The data of Experiment 2 showed that both D' and S' were highly correlated with S, D, and theta, and there was a high positive correlation between D' and S'. It was suggested that the direct-perception model is valid under some situations, but the taking-into-account model is not supported in any set of data.

Distance Perception↗
PubMed1994

Body image changes over the menstrual cycle in normal women.

Changes in body image across the menstrual cycle and the relationship between these changes and menstrual distress were investigated in an effort to identify determinants of body dissatisfaction. Twenty-six normally cycling women between 18-40 years of age and 90-115% of ideal body weight, with no history of an eating disorder, completed a series of body image measures and a measure of menstrual distress during three menstrual cycle phases: perimenstrual, follicular, and luteal. These phases were identified with serum levels of ovarian hormones and basal body temperature. Results indicated that body dissatisfaction as measured by the number of body-related negative thoughts and anxiety about appearance was significantly highest during the perimenstrual phase. In contrast, measures of body size perception remained stable. Several somatosensory and psychological symptoms of menstrual distress were significantly associated with body dissatisfaction during the perimenstrual phase including, water retention, autonomic reactivity, control, negative affect, and impaired concentration. This association of body dissatisfaction and menstrual distress strongly suggests that menstrual cycle changes play a significant role in body image.

Adolescent↗
PubMed1996

Differences in body image and depression among obese women with and without binge eating disorder.

Obese individuals with binge eating disorder (BED) differ from obese non-binge eating (NBE) individuals in a number of clinically relevant ways. This study examined attitudinal responses to various measures of body image in women seeking obesity treatment, by comparing NBE participants (n = 80) to those with BED (n = 48). It was hypothesized that women with BED would demonstrate greater attitudinal disturbance of body image compared to NBE individuals. It was further hypothesized that significant differences between groups would remain after statistically controlling for degree of depression. Consistent with the primary hypothesis, BED participants reported significantly increased attitudinal disturbance in body dissatisfaction and size perception compared to NBE participants. Although shared variance was observed between measures of depression and body image on some items, several aspects of increased body image disturbance remained after statistically controlling for depression. Treatment implications and recommendations for future research are discussed.

Adolescent↗