scholarly journals Gender and the Body Size and Shape Aftereffect: Implications for neural processing

2019 ◽  
Author(s):  
Kevin R. Brooks ◽  
Evelyn Baldry ◽  
Jon Mond ◽  
Dick stevenson ◽  
Deborah Mitchison ◽  
...  
Keyword(s):  
Body Size ◽  
Prolonged Exposure ◽  
The Body ◽  
Neural Mechanisms ◽  
Visual Adaptation ◽  
Neural Processing ◽  
Size And Shape ◽  
Before And After ◽  
Processing Body ◽  
Adaptation Model

Prolonged exposure to wide (thin) bodies causes a perceptual aftereffect such that subsequently-viewed bodies appear thinner (wider) than they actually are. This phenomenon is known as visual adaptation. We used the adaptation paradigm to examine the gender selectivity of the neural mechanisms encoding body size and shape. Observers adjusted female and male test bodies to appear normal-sized both before and after adaptation to bodies digitally altered to appear heavier or lighter. In Experiment 1, observers adapted simultaneously to bodies of each gender distorted in opposite directions, e.g. thin females and wide males. The direction of resultant aftereffects was contingent on the gender of the test stimulus, such that in this example female test bodies appeared wider while male test bodies appeared thinner. This indicates at least some separation of the neural mechanisms processing body size and shape for the two genders. In Experiment 2, adaptation involved either wide females, thin females, wide males or thin males. Aftereffects were present in all conditions, but were stronger when test and adaptation genders were congruent, suggesting some overlap in the tuning of gender-selective neural mechanisms. Given that visual adaptation has been implicated in real-world examples of body size and shape misperception (e.g. in anorexia nervosa or obesity), these results may have implications for the development of body image therapies based on the adaptation model.

scholarly journals Visual body size adaptation and estimation of tactile distance

2020 ◽  
Author(s):  
Regine Zopf ◽  
Veronika Kosourikhina ◽  
Kevin R. Brooks ◽  
Vince Polito ◽  
Ian Stephen
Keyword(s):  
Body Size ◽  
Adaptation Effect ◽  
The Body ◽  
Size Perception ◽  
Visual Adaptation ◽  
Social Environments ◽  
Body Images ◽  
Tactile Stimuli ◽  
Before And After ◽  
Adaptation Effects

Estimating the size of bodies is crucial for interactions with physical and social environments. Body size perception is malleable and can be altered using visual adaptation paradigms. However, it is unclear whether such visual adaptation effects also transfer to other modalities and influence, for example, the perception of tactile distances. In this study we employed a visual adaptation paradigm. Participants were exposed to images of expanded or contracted versions of self- or other-identity bodies. Before and after this adaptation they were asked to manipulate the width of body images to appear as “normal” as possible. We replicated an effect of visual adaptation, such that the body size selected as most “normal” was larger after exposure to expanded and thinner after exposure to contracted adaptation stimuli. In contrast, we did not find evidence that this adaptation effect transfers to distance estimates for paired tactile stimuli delivered to the abdomen. A Bayesian analysis showed that our data provide moderate evidence that there is no effect of visual body size adaptation on the estimation of spatial parameters in a tactile task. This suggests that visual body size adaptation effects do not transfer to somatosensory body size representations.

scholarly journals Gender and the Body Size Aftereffect: Implications for Neural Processing

2019 ◽  
Vol 13 ◽  
Author(s):  
Kevin R. Brooks ◽  
Evelyn Baldry ◽  
Jonathan Mond ◽  
Richard J. Stevenson ◽  
Deborah Mitchison ◽  
...  
Keyword(s):  
Body Size ◽  
The Body ◽  
Neural Processing

A study on 3D virtual body formation and deformation by body shape analysis

2019 ◽  
Vol 31 (6) ◽  
pp. 755-776
Author(s):  
Heekyung Jang ◽  
Jianhui Chen
Keyword(s):  
Body Size ◽  
Shape Analysis ◽  
Body Shape ◽  
The Body ◽  
Deformation Model ◽  
Content Type ◽  
Body Formation ◽  
Size And Shape ◽  
Virtual Body ◽  
Body Shape Analysis

Purpose The purpose of this paper is to use body shape analysis and develop a 3D virtual body formation and deformation model that can accurately express size and shape. Design/methodology/approach In this paper, 1,882 sets of direct measurement data of Korean women in their 20s (19–29 years) were analyzed. These data sets were sourced from the sixth and seventh “Size Korea” anthropometric survey data. Through body shape analysis, the authors classified them into seven body types and selected their representative bodies. A 2D image based on the height, breadth, depth and length was first formed, and the representative virtual body was modeled using the polygon technique. The authors calculated the grading ratios for each body type according to the clothing sizing system, and modified the virtual body size type by morphing technique. Findings In order to accurately evaluate the fit in a virtual fitting system, it is necessary to study the body size and shape of the target age; this makes it possible to form virtual body reflecting the size and shape. Originality/value In this paper, the authors propose a new 3D virtual body formation method that is more accurate in shape and size compared to the present system. Through this, it will be possible to grasp the accurate simulation state in the virtual fitting system, and thereby evaluate the accurate fit.

scholarly journals Looking at the Figures: Visual Adaptation as a Mechanism for Body-Size and -Shape Misperception

2019 ◽  
Vol 15 (1) ◽  
pp. 133-149 ◽  
Author(s):  
Kevin R. Brooks ◽  
Jonathan Mond ◽  
Deborah Mitchison ◽  
Richard J. Stevenson ◽  
Kirsten L. Challinor ◽  
...  
Keyword(s):  
Body Size ◽  
Media Representations ◽  
Health Interventions ◽  
Visual Adaptation ◽  
Social Scientists ◽  
Size And Shape ◽  
Medical Issues ◽  
Prevalence Of Obesity ◽  
Anxiety Depression ◽  
Insight Into

Many individuals experience body-size and -shape misperception (BSSM). Body-size overestimation is associated with body dissatisfaction, anxiety, depression, and the development of eating disorders in individuals who desire to be thinner. Similar symptoms have been noted for those who underestimate their muscularity. Conversely, individuals with high body mass indices (BMI) who underestimate their adiposity may not recognize the risks of or seek help for obesity-related medical issues. Although social scientists have examined whether media representations of idealized bodies contribute to the overestimation of fat or underestimation of muscle, other scientists suggest that increases in the prevalence of obesity could explain body-fat underestimation as a form of renormalization. However, these disparate approaches have not advanced our understanding of the perceptual underpinnings of BSSM. Recently, a new unifying account of BSSM has emerged that is based on the long-established phenomenon of visual adaptation, employing psychophysical measurements of perceived size and shape following exposure to “extreme” body stimuli. By inducing BSSM in the laboratory as an aftereffect, this technique is rapidly advancing our understanding of the underlying mental representation of human bodies. This nascent approach provides insight into real-world BSSM and may inform the development of therapeutic and public-health interventions designed to address such perceptual errors.

Hydrodynamic drag of diving birds: effects of body size, body shape and feathers at steady speeds

2001 ◽  
Vol 204 (9) ◽  
pp. 1547-1557 ◽  
Author(s):  
J. Lovvorn ◽  
G.A. Liggins ◽  
M.H. Borstad ◽  
S.M. Calisal ◽  
J. Mikkelsen
Keyword(s):  
Body Size ◽  
Laser Scanning ◽  
Body Shape ◽  
The Body ◽  
Hydrodynamic Drag ◽  
Energy Costs ◽  
Milling Machine ◽  
Size And Shape ◽  
High Speeds ◽  
Size Gradient

For birds diving to depths where pressure has mostly reduced the buoyancy of air spaces, hydrodynamic drag is the main mechanical cost of steady swimming. Drag is strongly affected by body size and shape, so such differences among species should affect energy costs. Because flow around the body is complicated by the roughness and vibration of feathers, feathers must be considered in evaluating the effects of size and shape on drag. We investigated the effects of size, shape and feathers on the drag of avian divers ranging from wing-propelled auklets weighing 75 g to foot-propelled eiders weighing up to 2060 g. Laser scanning of body surfaces yielded digitized shapes that were averaged over several specimens per species and then used by a milling machine to cut foam models. These models were fitted with casts of the bill area, and their drag was compared with that of frozen specimens. Because of the roughness and vibration of the feathers, the drag of the frozen birds was 2–6 times that of the models. Plots of drag coefficient (C(D)) versus Reynolds number (Re) differed between the model and the frozen birds, with the pattern of difference varying with body shape. Thus, the drag of cast models or similar featherless shapes can differ both quantitatively and qualitatively from that of real birds. On the basis of a new towing method with no posts or stings that alter flow or angles of attack, the dimensionless C(D)/Re curves differed among a size gradient of five auklet species (75–100g) with similar shapes. Thus, extrapolation of C(D)/Re curves among related species must be performed with caution. At lower speeds, the C(D) at a given Re was generally higher for long-necked birds that swim with their neck extended (cormorants, grebes, some ducks) than for birds that swim with their head retracted (penguins, alcids), but this trend was reversed at high speeds. Because swimming birds actually travel at a range of instantaneous speeds during oscillatory strokes, species variations in drag at different speeds must be considered in the context of accelerational stroking.

scholarly journals Effects of preweaning nutritional deprivation on basal metabolism and thermoregulatory thermogenesis in the rat

1986 ◽  
Vol 56 (3) ◽  
pp. 615-623 ◽  
Author(s):  
D. V. Muralidhara ◽  
P. S. Shetty
Keyword(s):  
Body Size ◽  
The Body ◽  
Metabolic Efficiency ◽  
Nutritional Rehabilitation ◽  
Adequate Diet ◽  
Nutritional Deprivation ◽  
Short Period ◽  
Body Weights ◽  
Before And After

1. Nutritional deprivation was induced preweaning in Wistar rats by increasing the litter size to sixteen, while paired litters with only five pups served as controls. The nutritionally deprived pups were rehabilitated after weaning by ad lib. access to an adequate diet.2. The body-weights and body lengths were significantly lower in the nutritionally deprived group and significant differences persisted even after 9 weeks of rehabilitation.3. The body temperature of the nutritionally deprived animals was significantly lower than that of their paired controls, both before and following nutritional rehabilitation, except for a short period after weaning when the nutritionally deprived animals were initially given the diet ad lib.4. The resting oxygen consumption of the nutritionally deprived animals was comparable to that of the controls when corrected for metabolic body size, both before and after weaning. Noradrenaline-stimulated increase in 02 consumption (non-shivering thermogenesis; NST) was reduced by 50% at weaning in the nutritionally deprived animals and returned to levels comparable to those of controls within a short period of rehabilitation.5. The decrease in NST capacity seen in the nutritionally deprived animals was associated with an inability to thermoregulate when exposed to cold (5°), resulting in death. Cold-induced thermogenesis (CIT) also reappeared soon after nutritional rehabilitation.6. Reduction in metabolic rate, NST and CIT seen in the animals nutritionally deprived preweaning was short-lived and disappeared soon after nutritional rehabilitation. Rapid reversal of these physiological changes indicates that they do not confer any long-term benefit or change in metabolic efficiency and are unlike the changes in body size and growth which do not completely recover following nutritional rehabilitation.

Can Health and Wellbeing Come in All Shapes and Sizes? Dieting: The Big Con. A Harm Minimisation Program

2002 ◽  
Vol 8 (2) ◽  
pp. 39
Author(s):  
Susan Mann ◽  
Helen Harmer
Keyword(s):  
Body Image ◽  
Body Size ◽  
Healthy Lifestyle ◽  
The Body ◽  
Health Promotion Program ◽  
Harm Minimisation ◽  
Size And Shape ◽  
Community Health Nurses ◽  
Ideal Body Image ◽  
The Media

Stress, low self-esteem, mental illness issues and physical debility are recognised outcomes for women striving for an ideal body image (Paxton 2000). However, the prevailing discourse remains that healthy lifestyle relates to specific body size and shape. This message is evident throughout the media, which clearly links healthy people to slim bodies imbued with youth, vitality and good looks. Community health nurses, concerned for women in the community who were deemed overweight by the Body Mass Index scale and engaged in cyclic patterns of dieting, initiated a health promotion program, aimed at challenging such discourse. A multidisciplinary group involving expertise from nursing, nutrition, psychology and community members was established to develop and run a program for women, which focused on body image, healthy lifestyles and eating patterns. This paper discusses the outcomes of these programs, which challenge the argument that body size and shape determines health.

scholarly journals Beyond BMI for self-estimates of body size and shape: A new method for developing stimuli correctly calibrated for body composition

2020 ◽  
Author(s):  
Nadia Maalin ◽  
Sophie Mohamed ◽  
Robin S. S. Kramer ◽  
Piers L. Cornelissen ◽  
Daniel Martin ◽  
...  
Keyword(s):  
Eating Disorders ◽  
Body Composition ◽  
Body Size ◽  
Body Shape ◽  
Two Dimensions ◽  
The Body ◽  
Assessment Tools ◽  
Self Assessment ◽  
Size And Shape ◽  
Shape And Size

Abstract Accurate self-assessment of body shape and size plays a key role in the prevention, diagnosis, and treatment of both obesity and eating disorders. These chronic conditions cause significant health problems, reduced quality of life, and represent a major problem for health services. Variation in body shape depends on two aspects of composition: adiposity and muscularity. However, most self-assessment tools are unidimensional. They depict variation in adiposity only, typically quantified by the body mass index. This can lead to substantial, and clinically meaningful, errors in estimates of body shape and size. To solve this problem, we detail a method of creating biometrically valid body stimuli. We obtained high-resolution 3D body shape scans and composition measures from 397 volunteers (aged 18–45 years) and produced a statistical mapping between the two. This allowed us to create 3D computer-generated models of bodies, correctly calibrated for body composition (i.e., muscularity and adiposity). We show how these stimuli, whose shape changes are based on change in composition in two dimensions, can be used to match the body size and shape participants believe themselves to have, to the stimulus they see. We also show how multivariate multiple regression can be used to model shape change predicted by these 2D outcomes, so that participants’ choices can be explained by their measured body composition together with other psychometric variables. Together, this approach should substantially improve the accuracy and precision with which self-assessments of body size and shape can be made in obese individuals and those suffering from eating disorders.

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