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Gumančík J, Cornelissen PL, Brokjøb LG, Ridley BJ, McCarty K, Tovée MJ, Cornelissen KK. Testing the validity of online psychophysical measurement of body image perception. PLoS One 2024; 19:e0302747. [PMID: 38857270 PMCID: PMC11164378 DOI: 10.1371/journal.pone.0302747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 04/10/2024] [Indexed: 06/12/2024] Open
Abstract
This body image study tests the viability of transferring a complex psychophysical paradigm from a controlled in-person laboratory task to an online environment. 172 female participants made online judgements about their own body size when viewing images of computer-generated female bodies presented in either in front-view or at 45-degrees in a method of adjustment (MOA) paradigm. The results of these judgements were then compared to the results of two laboratory-based studies (with 96 and 40 female participants respectively) to establish three key findings. Firstly, the results show that the accuracy of online and in-lab estimates of body size are comparable, secondly that the same patterns of visual biases in judgements are shown both in-lab and online, and thirdly online data shows the same view-orientation advantage in accuracy in body size judgements as the laboratory studies. Thus, this study suggests that that online sampling potentially represents a rapid and accurate way of collecting reliable complex behavioural and perceptual data from a more diverse range of participants than is normally sampled in laboratory-based studies. It also offers the potential for designing stratified sampling strategies to construct a truly representative sample of a target population.
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Affiliation(s)
- Jiří Gumančík
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Piers L. Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Lise Gulli Brokjøb
- Department of Psychology, The Artic University of Norway, Tromsø, Norway
| | - Bethany J. Ridley
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Kristofor McCarty
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Martin J. Tovée
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Katri K. Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
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Jones AR, Mann KD, Cutler LR, Pearce MS, Tovée MJ, Ells LJ, Araujo-Soares V, Arnott B, Harris JM, Adamson AJ. A Randomised Control Trial Investigating the Efficacy of the MapMe Intervention on Parental Ability to Correctly Categorise Overweight in Their Child and the Impact on Child BMI Z-Score Change at 1 Year. CHILDREN (BASEL, SWITZERLAND) 2023; 10:1577. [PMID: 37761538 PMCID: PMC10528244 DOI: 10.3390/children10091577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 09/08/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023]
Abstract
Research suggests parental ability to recognise when their child has overweight is limited. It is hypothesised that recognition of child overweight/obesity is fundamental to its prevention, acting as a potential barrier to parental action to improve their child's health-related behaviours and/or help seeking. The purpose of this study was to investigate the efficacy of an intervention (MapMe) to improve parental ability to correctly categorise their child as having overweight one-month post-intervention, and reduce child body mass index (BMI) z-score 12 months post-intervention. MapMe consists of body image scales of known child BMI and information on the consequences of childhood overweight, associated health-related behaviours and sources of support. We conducted a three-arm (paper-based MapMe, web-based MapMe and control) randomised control trial in fifteen English local authority areas with parents/guardians of 4-5- and 10-11-year-old children. Parental categorisation of child weight status was assessed using the question 'How would you describe your child's weight at the moment?' Response options were: underweight, healthy weight, overweight, and very overweight. Child weight status and BMI z-scores were calculated using objectively measured height and weight data and UK90 clinical thresholds. There was no difference in the percentage of parents correctly categorising their child as having overweight/very overweight (n = 264: 41% control, 48% web-based, and 43% paper-based, p = 0.646). BMI z-scores were significantly reduced for the intervention group at 12 months post-intervention compared to controls (n = 338, mean difference in BMI z-score change -0.11 (95% CI -0.202 to -0.020, p = 0.017). MapMe was associated with a decrease in BMI z-score 12 months post-intervention, although there was no direct evidence of improved parental ability to correctly categorise child overweight status. Further work is needed to replicate these findings in a larger sample of children, investigate mechanisms of action, and determine the use of MapMe as a public health initiative.
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Affiliation(s)
- Angela R. Jones
- Population Health Sciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK (M.S.P.); (B.A.); (A.J.A.)
- Human Nutrition and Exercise Research Centre, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Kay D. Mann
- Health Capital Division, Queensland Health, 33 Charlotte Street, Brisbane, QLD 4000, Australia;
| | - Laura R. Cutler
- Population Health Sciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK (M.S.P.); (B.A.); (A.J.A.)
- Human Nutrition and Exercise Research Centre, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
| | - Mark S. Pearce
- Population Health Sciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK (M.S.P.); (B.A.); (A.J.A.)
| | - Martin J. Tovée
- Health and Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, UK;
| | - Louisa J. Ells
- School of Clinical & Applied Sciences, Leeds Beckett University, Leeds LS1 3HE, UK;
| | - Vera Araujo-Soares
- Center for Preventive Medicine and Digital Health, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany;
| | - Bronia Arnott
- Population Health Sciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK (M.S.P.); (B.A.); (A.J.A.)
| | - Julie M. Harris
- School of Psychology and Neuroscience, University of St Andrews, St Andrews KY16 9TS, UK;
| | - Ashley J. Adamson
- Population Health Sciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK (M.S.P.); (B.A.); (A.J.A.)
- Human Nutrition and Exercise Research Centre, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK
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Groves V, Ridley BJ, Cornelissen PL, Maalin N, Mohamed S, Kramer RSS, McCarty K, Tovée MJ, Cornelissen KK. Men's perception of current and ideal body composition and the influence of media internalization on body judgements. Front Psychol 2023; 14:1116686. [PMID: 37205060 PMCID: PMC10185840 DOI: 10.3389/fpsyg.2023.1116686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 03/31/2023] [Indexed: 05/21/2023] Open
Abstract
Introduction To determine men's body ideals and the factors that influence these choices, this study used a matrix of computer generated (CG) male bodies (based on an analysis of 3D scanned real bodies) which independently varied in fat and muscle content. Methods Two hundred and fifty-eight male participants completed a range of psychometric measures to index body concerns and body ideal internalization and then chose the CG body that best reflected their own current body, as well as the body that reflected their personal ideal. A subset of participants was then retested to check that these judgements were stable over time. Results While judgements of the ideal body seem to be influenced by a shared appearance ideal, the degree to which this ideal was internalized showed significant variability between participants. The effect of this internalization was reflected in the difference between the estimated current body and the ideal. Discussion Higher internalization led to a preference for higher muscle and lower fat content. This preference was most marked for fat content, although reducing adiposity also made the underlying musculature more salient. Additionally, the ideal body composition was modulated by the composition the participant believed his current body had (i.e., it seemed that a participant's ideal body was anchored by what they believed to be their current body and what change was possible from this starting point).
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Affiliation(s)
- Vicki Groves
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Bethany J. Ridley
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Piers L. Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Nadia Maalin
- Department of Psychology, Birmingham City University, Birmingham, United Kingdom
| | - Sophie Mohamed
- Aberdeen Royal Infirmary, NHS Grampian, Aberdeen, United Kingdom
| | | | - Kristofor McCarty
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Martin J. Tovée
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Katri K. Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
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Evans EH, Tovée MJ, Hancock PJB, Cornelissen PL. How do looking patterns, anti-fat bias, and causal weight attributions relate to adults' judgements of child weight? Body Image 2023; 44:9-23. [PMID: 36413890 DOI: 10.1016/j.bodyim.2022.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 11/01/2022] [Accepted: 11/01/2022] [Indexed: 11/21/2022]
Abstract
Prevailing weight-normative approaches to health pressure adults to visually categorise children's weight, despite little understanding of how such judgements are made. There is no evidence this strategy improves child health, and it may harm children with higher weights. To understand decision-making processes and identify potential mechanisms of harm we examined perceptual and attitudinal factors involved in adults' child weight category judgements. Eye movements of 42 adults were tracked while categorizing the weight of 40 computer-generated images of children (aged 4-5 & 10-11 years) varying in size. Questionnaires assessed child-focused weight bias and causal attributions for child weight. Participants' eye movement patterns resembled those previously reported for adult bodies. Categorisation data showed a perceptual bias towards the 'mid-range' category. For higher weight stimuli, participants whose category judgements most closely matched the stimulus's objective weight had higher child-focused anti-fat bias and weaker genetic attributions for child weight - i.e,. adults who 'label' higher weight in children in line with BMI categories report more stigmatising beliefs about such children, suggesting a possible mechanism of harm. Overall, adults' judgements reflect both unalterable perceptual biases and potentially harmful attitudinal factors, calling into question the feasibility and appropriateness of public health efforts to promote visual child weight categorisation.
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Affiliation(s)
- Elizabeth H Evans
- Department of Psychology, Durham University, Durham, United Kingdom.
| | - Martin J Tovée
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | | | - Piers L Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
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Turnbull G, Lego S, Kennedy BL, Alexi J, Li YR, Engel MM, Mann G, Bayliss DM, Farrell S, Bell J. Sizing up the crowd: Assessing spatial integration difficulties in body size judgements across eating disorder symptomatology. Front Psychol 2023; 13:1003250. [PMID: 36687820 PMCID: PMC9853910 DOI: 10.3389/fpsyg.2022.1003250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/30/2022] [Indexed: 01/07/2023] Open
Abstract
Introduction Body size judgements are frequently biased, or inaccurate, and these errors are further exaggerated for individuals with eating disorders. Within the eating disorder literature, it has been suggested that exaggerated errors in body size judgements are due to difficulties with integration. Across two experiments, we developed a novel integration task, named the Ebbinghaus Illusion for Bodies in Virtual Reality (VR), to assess whether nearby bodies influence the perceived size of a single body. VR was used to simulate the appearance of a small crowd around a central target body. Method and Results In Experiment 1 (N = 412), participants were required to judge the size of a central female target within a crowd. Experiment 1 revealed an Ebbinghaus Illusion, in which a central female appeared larger when surrounded by small distractors, but comparatively smaller when surrounded by large distractors. In other words, the findings of Experiment 1 demonstrate that surrounding crowd information is integrated when judging an individual's body size; a novel measure of spatial integration (i.e., an Ebbinghaus Illusion for Bodies in VR). In Experiment 2 (N = 96), female participants were selected based on high (n = 43) and low (n = 53) eating disorder symptomatology. We examined whether the magnitude of this illusion would differ amongst those with elevated versus low eating disorder symptomatology, in accordance with weak central coherence theory, with the high symptomatology group displaying less spatial integration relative to the low group. The results of Experiment 2 similarly found an Ebbinghaus Illusion for Bodies in VR. However, illusion magnitude did not vary across high and low symptomatology groups. Discussion Overall, these findings demonstrate that surrounding crowd information is integrated when judging individual body size; however, those with elevated eating disorder symptomatology did not show any integration deficit on this broader measure of spatial integration.
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Affiliation(s)
- Georgia Turnbull
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia,*Correspondence: Georgia Turnbull,
| | - Sophia Lego
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
| | - Briana L. Kennedy
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
| | - Joanna Alexi
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
| | - Yanqi R. Li
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
| | - Manja M. Engel
- Faculty of Social and Behavioural Sciences, Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, Netherlands
| | - Georgina Mann
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
| | - Donna M. Bayliss
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
| | - Simon Farrell
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
| | - Jason Bell
- School of Psychological Science, University of Western Australia, Crawley, WA, Australia
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Althunibat OY, Saghir SAM, Aladaileh SH, Rawadieh A. The impact of weight loss diet programs on anemia, nutrient deficiencies, and organ dysfunction markers among university female students: A cross-sectional study. ELECTRONIC JOURNAL OF GENERAL MEDICINE 2023. [DOI: 10.29333/ejgm/12675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Practicing restricted weight loss diet programs (WLDPs) without proper supervision can result in nutritional deficiency, which can lead to the development of several nutritional disorders. The current cross-sectional study aimed to investigate the impact of WLDPs practiced by university female students on the prevalence of micronutrient deficiencies, anemia, and organs dysfunction, and to assess the association of identified anomalies with dieting practices and dietary habits of university female students. A total of 185 (105 dieting and 80 non-dieting) volunteers’ female students at Al-Hussein Bin Talal University participated in this study. After the participants answered a questionnaire, blood samples were collected for hematological and biochemical analysis, and the body mass index (BMI) was determined. The results show that there were no significant differences between dieting and non-dieting groups in biochemical markers of kidney and liver functions as well as serum levels of copper, zinc, and folate. On the other hand, dieting participants exhibited significantly lower level of hemoglobin, serum ferritin, iron, and vitamin B12 than encounter group (p<0.05). Attempting WLDPs significantly increased the prevalence of anemia (46.7%), iron deficiency (57.1%), and iron deficiency anemia (IDA) (41.9%), comparing to non-dieting students (28.7%, 33.8%, and 15.0%, respectively) (p<0.005). Chi-square test showed that the development of anemia among dieting girls was significantly dependence of several factors including BMI category, source and duration of the diet programs, and skipping breakfast (p<0.05). In conclusion, young girls attempting WLDPs without professional guidance are more prone to the risk of nutrients deficiencies and the development nutritional disorders like IDA. An educational program should be employed to teach young females on when and how to adopt healthy WLDPs.
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Affiliation(s)
- Osama Y. Althunibat
- Department of Medical Analysis, Princess Aisha Bint Al-Hussein College of Nursing and Medical Sciences, Al-Hussein Bin Talal University, Ma’an, JORDAN
| | - Sultan Ayesh Mohammed Saghir
- Department of Medical Analysis, Princess Aisha Bint Al-Hussein College of Nursing and Medical Sciences, Al-Hussein Bin Talal University, Ma’an, JORDAN
| | - Saleem Hmoud Aladaileh
- Department of Medical Analysis, Princess Aisha Bint Al-Hussein College of Nursing and Medical Sciences, Al-Hussein Bin Talal University, Ma’an, JORDAN
- Department of Biology, College of Science, Al-Hussein Bin Talal University, Ma’an, JORDAN
| | - Atikah Rawadieh
- Department of Medical Analysis, Princess Aisha Bint Al-Hussein College of Nursing and Medical Sciences, Al-Hussein Bin Talal University, Ma’an, JORDAN
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Ridley BJ, Cornelissen PL, Maalin N, Mohamed S, Kramer RSS, McCarty K, Tovée MJ. The degree to which the cultural ideal is internalized predicts judgments of male and female physical attractiveness. Front Psychol 2022; 13:980277. [PMID: 36337567 PMCID: PMC9626828 DOI: 10.3389/fpsyg.2022.980277] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 09/13/2022] [Indexed: 04/14/2024] Open
Abstract
We used attractiveness judgements as a proxy to visualize the ideal female and male body for male and female participants and investigated how individual differences in the internalization of cultural ideals influence these representations. In the first of two studies, male and female participants judged the attractiveness of 242 male and female computer-generated bodies which varied independently in muscle and adipose. This allowed us to map changes in attractiveness across the complete body composition space, revealing single peaks for the attractiveness of both men and women. In the second study, we asked our participants to choose the most attractive male and female bodies in a method of adjustment task in which they could independently vary muscle and adipose to create the most attractive body. We asked whether individual differences in internalization of cultural ideals, drive for muscularity, eating disorder symptomatology and depressive symptoms could systematically shift the location of peak attractiveness in body composition space. We found a clear preference by both genders for a male body with high muscle and low adipose, and a toned, low adipose female body. The degree of internalization of cultural ideals predicted large individual differences in the composition of the most attractive bodies.
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Affiliation(s)
- Bethany J. Ridley
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Piers L. Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Nadia Maalin
- Department of Psychology, Birmingham City University, Birmingham, United Kingdom
| | - Sophie Mohamed
- Aberdeen Royal Infirmary, NHS Grampian, Aberdeen, United Kingdom
| | | | - Kristofor McCarty
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Martin J. Tovée
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
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Thornborrow T, Evans EH, Tovee MJ, Boothroyd LG. Sociocultural drivers of body image and eating disorder risk in rural Nicaraguan women. J Eat Disord 2022; 10:133. [PMID: 36068623 PMCID: PMC9450464 DOI: 10.1186/s40337-022-00656-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/14/2022] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Technological and economic globalisation has been suggested as a cause of increasing rates of body dissatisfaction and eating disorders globally, especially as regards the impact of mass media on internalised body ideals. This process is rarely observed in action, however. The current work investigates multiple aspects of body ideals, body image, sociocultural attitudes and eating attitudes in 62 Creole and Mestizo women living in communities at differing stages of technological development on the Caribbean coast of Nicaragua METHOD/RESULTS: In Study 1, women used 3D avatar software to create their own 'ideal' body without the constraints of ready-made stimuli. Analyses of resulting avatars showed that components of the ideal body shape (upper and lower body curvaceousness) but not body size (body mass) were associated with levels of film and television consumption. In Study 2, women completed measures of variables in the sociocultural model of eating disorder risk. As expected, body dissatisfaction mediated the relationship between internalisation of sociocultural body ideals and pathological eating attitudes. In contrast, body appreciation reduced pathological eating attitudes, via reduced body dissatisfaction. Finally, Study 3 measured sociocultural influences, body image and eating attitudes at 2 or 3 timepoints per woman; body dissatisfaction covaried with pathological eating attitudes across time. Ethnicity varied in its effects across studies. DISCUSSION Together these data show that even at early stages of media acculturation, women may show similar patterns of association between sociocultural internalisation, body dissatisfaction and eating disorder risk as in high income nations. However, they also demonstrate unique aspects of this population's body shape ideals, and the independent protective effect of body appreciation.
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Affiliation(s)
- T Thornborrow
- School of Psychology, University of Lincoln, Brayford Pool, Lincoln, LN6 7TS, Lincolnshire, UK.
| | - E H Evans
- Department of Psychology, Durham University, South Road, Durham, DH1 3LE, UK
| | - M J Tovee
- Department of Psychology, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK
| | - L G Boothroyd
- Department of Psychology, Durham University, South Road, Durham, DH1 3LE, UK.
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Cornelissen KK, Brokjøb LG, Gumančík J, Lowdon E, McCarty K, Irvine KR, Tovée MJ, Cornelissen PL. The Effect of Own Body Concerns on Judgments of Other Women’s Body Size. Front Psychol 2022; 13:888904. [PMID: 35602723 PMCID: PMC9120952 DOI: 10.3389/fpsyg.2022.888904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 03/24/2022] [Indexed: 11/13/2022] Open
Abstract
We investigated the relationships between healthy women’s estimates of their own body size, their body dissatisfaction, and how they subjectively judge the transition from normal to overweight in other women’s bodies (the “normal/overweight” boundary). We propose two complementary hypotheses. In the first, participants compare other women to an internalized Western “thin ideal,” whose size reflects the observer’s own body dissatisfaction. As dissatisfaction increases, so the size of their “thin ideal” reduces, predicting an inverse relationship between the “normal/overweight” boundary and participants’ body dissatisfaction. Alternatively, participants judge the size of other women relative to the body size they believe they have. For this implicit or explicit social comparison, the participant selects a “normal/overweight” boundary that minimizes the chance of her making an upward social comparison. So, the “normal/overweight” boundary matches or is larger than her own body size. In an online study of 129 healthy women, we found that both opposing factors explain where women place the “normal/overweight” boundary. Increasing body dissatisfaction leads to slimmer judgments for the position of the “normal/overweight” boundary in the body mass index (BMI) spectrum. Whereas, increasing overestimation by the observer of their own body size shifts the “normal/overweight” boundary toward higher BMIs.
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Affiliation(s)
- Katri K. Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Lise Gulli Brokjøb
- Department of Psychology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Jiří Gumančík
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Ellis Lowdon
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Kristofor McCarty
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Kamila R. Irvine
- School of Psychology, College of Social Science, University of Lincoln, Lincolnshire, United Kingdom
| | - Martin J. Tovée
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Piers Louis Cornelissen
- Department of Psychology, Northumbria University, Newcastle upon Tyne, United Kingdom
- *Correspondence: Piers Louis Cornelissen,
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10
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D'Amour S, Alexe D, Harris LR. Changes in the perceived size of the body following exposure to distorted self-body images. ROYAL SOCIETY OPEN SCIENCE 2022; 9:210722. [PMID: 35462776 PMCID: PMC9019518 DOI: 10.1098/rsos.210722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
Inaccurate perceptions, such as under- or over-estimation of body size are often found in clinical eating disorder populations but have recently been shown also in healthy people. However, it is not yet clear how body size perception may be affected when the internal body representation is manipulated. In this study, visual adaptation was used to investigate whether exposure to distorted visual feedback alters the representation of body size and how long any such effects might last. Participants were exposed for five minutes to a distorted life-size image of themselves that was either 20% wider or 20% narrower than their normal size. Accuracy was measured using our novel psychophysical method that taps into the implicit body representation. The accuracy of the representation was assessed at 6, 12 and 18 min following exposure to adaptation. Altered visual feedback caused changes in participants' judgements of their body size: adapting to a wider body resulted in size overestimation whereas underestimations occurred after adapting to a narrower body. These distortions lasted throughout testing and did not fully return back to normal within 18 min. The results are discussed in terms of the emerging literature indicating that the internal representation of the body is dynamic and flexible.
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Affiliation(s)
- Sarah D'Amour
- Centre for Vision Research, York University, Toronto, Canada
| | - Deborah Alexe
- Centre for Vision Research, York University, Toronto, Canada
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11
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Turnbull G, Alexi J, Mann G, Li Y, Engel M, Bayliss DM, Farrell S, Bell J. EXPRESS: The Influence of Three-Dimensional Cues on Body Size Judgements. Q J Exp Psychol (Hove) 2022; 75:2318-2331. [PMID: 35034530 DOI: 10.1177/17470218221076850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Research has shown that body size judgements are frequently biased, or inaccurate. Critically, judgement biases are further exaggerated for individuals with eating disorders, a finding that has been attributed to difficulties integrating body features into a perceptual whole. However, current understanding of which body features are integrated when judging body size is lacking. In this study, we examine whether individuals integrate three-dimensional (3D) cues to body volume when making body size judgements. Computer-generated body stimuli were presented in a 3D Virtual Reality (VR) environment. Participants (N = 412) were randomly assigned to one of two conditions: in one condition the to-be-judged body was displayed binocularly (containing 3D cues to body volume), in the other, bodies were presented monocularly (2D cues only). Across 150 trials, participants were required to make a body size judgement of a target female body from a third-person point of view using an unmarked visual analogue scale (VAS). It was found that 3D cues significantly influenced body size judgements. Namely, thin 3D bodies were judged smaller, and overweight 3D bodies were judged larger, than their 2D counterpart. Furthermore, to reconcile these effects, we present evidence that the two perceptual biases, regression to the mean and serial dependence, were reduced by the additional 3D feature information. Our findings increase our understanding of how body size is perceptually encoded and creates testable predictions for clinical populations exhibiting integration difficulties.
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Affiliation(s)
- Georgia Turnbull
- School of Psychological Science, University of Western Australia (M304), 35 Stirling Highway, Crawley WA 6009, Australia 2720
| | - Joanna Alexi
- School of Psychological Science, University of Western Australia (M304), 35 Stirling Highway, Crawley WA 6009, Australia 2720
| | - Georgina Mann
- School of Psychological Science, University of Western Australia (M304), 35 Stirling Highway, Crawley WA 6009, Australia 2720
| | - Yanqi Li
- School of Psychological Science, University of Western Australia (M304), 35 Stirling Highway, Crawley WA 6009, Australia 2720
| | - Manja Engel
- Utrecht University, Faculty of Social and Behavioural Sciences, Experimental Psychology/Helmholtz Institute. Heidelberglaan 1, 3584 CS Utrecht, Netherlands 8125
| | - Donna M Bayliss
- School of Psychological Science, University of Western Australia (M304), 35 Stirling Highway, Crawley WA 6009, Australia 2720
| | - Simon Farrell
- School of Psychological Science, University of Western Australia (M304), 35 Stirling Highway, Crawley WA 6009, Australia 2720
| | - Jason Bell
- School of Psychological Science, University of Western Australia (M304), 35 Stirling Highway, Crawley WA 6009, Australia 2720
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12
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Wildman A, Ramsey R. Estimating the effects of trait knowledge on social perception. Q J Exp Psychol (Hove) 2021; 75:969-987. [PMID: 34491145 DOI: 10.1177/17470218211047447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Research in social cognition has predominantly investigated perceptual and inferential processes separately; however, real-world social interactions usually involve integration between person inferences (e.g., generous, selfish) and the perception of physical appearance (e.g., thin, tall). Therefore, in the current work, we investigated the integration of different person-relevant signals, by estimating the extent to which bias in one social information processing system influences another. Following an initial stimulus-validation experiment (Experiment 1, N = 55), two further pre-registered experiments (Experiments 2, N = 55 and 3; N = 123) employed a priming paradigm to measure the effects of extraversion-diagnostic information on subsequent health and body-size judgements of a target body. The results were consistent across both priming experiments and supported our predictions: compared to trait-neutral control statements, extraversion-diagnostic statements increased judgements of health and decreased those of body size. As such, we show that trait-based knowledge does not only influence mappings towards similar types of person judgements, such as health judgements. Rather, even a brief re-configuration of trait-space alters mappings towards non-trait judgements, which are based on body size and shape. The results complement prior neuroimaging findings that showed functional interactions between the body-selective brain regions in the ventral visual stream and the theory of mind network when forming impressions of others. Therefore, we provide a functional signature of how distinct information processing units exchange signals and integrate information to form impressions. Overall, the current study underscores the value of behavioural work in complementing neuroscience research when investigating the role and properties of functional integration during impression formation. In addition, it stresses the potential limitations of an over-reliance on studying separate systems in isolation.
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Affiliation(s)
- Andrew Wildman
- Wales Institute for Cognitive Neuroscience, School of Psychology, Bangor University, Bangor, UK
| | - Richard Ramsey
- Department of Psychology, Macquarie University, Sydney, NSW, Australia
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13
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Women's self-estimates of body size are more accurate and precise when made with three-quarter view than front-view stimuli. Body Image 2021; 38:171-180. [PMID: 33894422 DOI: 10.1016/j.bodyim.2021.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 04/06/2021] [Accepted: 04/07/2021] [Indexed: 11/21/2022]
Abstract
Recently, Cornelissen, Cornelissen, Groves, McCarty and Tovée (2018) asked which image orientations (e.g. front-, side-, or three-quarter view) are most appropriate for tasks which are used for self-estimates of body size and shape. Based on psychophysical measurements, they showed that front view stimuli showed substantially poorer content validity compared to side- and three-quarter view stimuli. Here, we tested the real-world consequences of Cornelissen et al.'s (2018) findings. We carried out a body size self-estimation task in a sample of healthy adult women, once with front view stimuli, and once with three-quarter view stimuli. The order in which front- and three-quarter view tasks were carried out was randomized across participants. Compared to three-quarter view stimuli, we found that: a) the precision of participants' judgements was worse with front view stimuli, and b) that front view stimuli led to over-estimation of body size by ∼1.7 BMI units. While these results need to be replicated, they do suggest that careful consideration needs to be given to stimulus orientation in future studies.
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14
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Chan AWY, Noles DL, Utkov N, Akbilgic O, Smith W. Misalignment between perceptual boundaries and weight categories reflects a new normal for body size perception. Sci Rep 2021; 11:10442. [PMID: 34001935 PMCID: PMC8129102 DOI: 10.1038/s41598-021-89533-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 04/20/2021] [Indexed: 12/14/2022] Open
Abstract
Combatting the current global epidemic of obesity requires that people have a realistic understanding of what a healthy body size looks like. This is a particular issue in different population sub-groups, where there may be increased susceptibility to obesity-related diseases. Prior research has been unable to systematically assess body size judgement due to a lack of attention to gender and race; our study aimed to identify the contribution of these factors. Using a data-driven multi-variate decision tree approach, we varied the gender and race of image stimuli used, and included the same diversity among participants. We adopted a condition-rich categorization visual task and presented participants with 120 unique body images. We show that gender and weight categories of the stimuli affect accuracy of body size perception. The decision pattern reveals biases for male bodies, in which participants showed an increasing number of errors from leaner to bigger bodies, particularly under-estimation errors. Participants consistently mis-categorized overweight male bodies as normal weight, while accurately categorizing normal weight. Overweight male bodies are now perceived as part of an expanded normal: the perceptual boundary of normal weight has become wider than the recognized BMI category. For female bodies, another intriguing pattern emerged, in which participants consistently mis-categorized underweight bodies as normal, whilst still accurately categorizing normal female bodies. Underweight female bodies are now in an expanded normal, in opposite direction to that of males. Furthermore, an impact of race type and gender of participants was also observed. Our results demonstrate that perceptual weight categorization is multi-dimensional, such that categorization decisions can be driven by ultiple factors.
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Affiliation(s)
- Annie W Y Chan
- Division of Psychology, Department of Life Sciences, Centre for Cognitive Neuroscience, Brunel University London, Gaskell Building, Room 219, Uxbridge, UB8 3PH, UK.
| | - Danielle L Noles
- School of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Nathan Utkov
- Department of Bioinformatics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Oguz Akbilgic
- Department of Health Informatics and Data Science, Parkinson School of Health Informatics and Public Health, Loyola University Chicago, Maywood, IL, USA
| | - Webb Smith
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, USA
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15
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Cazzato V, Walters ER, Urgesi C. Associations of observer's gender, Body Mass Index and internalization of societal beauty ideals to visual body processing. PSYCHOLOGICAL RESEARCH 2021; 85:3026-3039. [PMID: 33433640 PMCID: PMC8476362 DOI: 10.1007/s00426-020-01471-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Accepted: 12/24/2020] [Indexed: 11/25/2022]
Abstract
We examined whether visual processing mechanisms of the body of conspecifics are different in women and men and whether these rely on westernised socio-cultural ideals and body image concerns. Twenty-four women and 24 men performed a visual discrimination task of upright or inverted images of female or male bodies and faces (Experiment 1) and objects (Experiment 2). In Experiment 1, both groups of women and men showed comparable abilities in the discrimination of upright and inverted bodies and faces. However, the gender of the human stimuli yielded different effects on participants’ performance, so that female faces, and male bodies appeared to be processed less configurally than female bodies and male faces, respectively. Interestingly, the reduction of configural processing for male bodies was significantly predicted by participants’ Body Mass Index (BMI) and their level of internalization of muscularity. Our findings suggest that configural visual processing of bodies and faces in women and men may be linked to a selective attention to detail needed for discriminating salient physical (perhaps sexual) cues of conspecifics. Importantly, BMI and muscularity internalization of beauty ideals may also play a crucial role in this mechanism.
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Affiliation(s)
- Valentina Cazzato
- School of Psychology, Faculty of Health, Liverpool John Moores University, Liverpool, UK.
| | | | - Cosimo Urgesi
- Department of Languages and Literatures, Communication, Education and Society, University of Udine, Udine, Italy.,Scientific Institute, IRCCS E. Medea, Bosisio Parini, Lecco, Italy
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16
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D'Amour S, Harris LR. The Representation of Body Size: Variations With Viewpoint and Sex. Front Psychol 2020; 10:2805. [PMID: 31920848 PMCID: PMC6929680 DOI: 10.3389/fpsyg.2019.02805] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Accepted: 11/28/2019] [Indexed: 11/22/2022] Open
Abstract
Perceived body size is a fundamental construct that reflects our knowledge of self and is important for all aspects of perception, yet how we perceive our bodies and how the body is represented in the brain is not yet fully understood. In order to understand how the brain perceives and represents the body, we need an objective method that is not vulnerable to affective or cognitive influences. Here, we achieve this by assessing the accuracy of full-body size perception using a novel psychophysical method that taps into the implicit body representation for determining perceived size. Participants were tested with life-size images of their body as seen from different viewpoints with the expectation that greater distortions would occur for unfamiliar views. The Body Shape Questionnaire was also administered. Using a two-alternative forced choice design, participants were sequentially shown two life-size images of their whole body dressed in a standardized tight-fitting outfit seen from the front, side, or back. In one image, the aspect ratio (with the horizontal or vertical dimension fixed) was varied using an adaptive staircase, while the other was undistorted. Participants reported which image most closely matched their own body size. The staircase honed in on the distorted image that was equally likely as the undistorted photo to be judged as matching their perception of themselves. From this, the perceived size of their internal body representation could be calculated. Underestimation of body width was found when the body was viewed from the front or back in both sexes. However, females, but not males, overestimated their width when the body was viewed from the side. Height was perceived accurately in all views. These findings reveal distortions in perceived size for healthy populations and show that both viewpoint and sex matter for the implicit body representation. Though the back view of one’s body is rarely–if ever–seen, perceptual distortions were the same as for the front view. This provides insight into how the brain might construct its representation of three-dimensional body shape.
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Affiliation(s)
- Sarah D'Amour
- Department of Psychology, Centre for Vision Research, York University, Toronto, ON, Canada
| | - Laurence R Harris
- Department of Psychology, Centre for Vision Research, York University, Toronto, ON, Canada
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17
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Brooks KR, Mond J, Mitchison D, Stevenson RJ, Challinor KL, Stephen ID. Looking at the Figures: Visual Adaptation as a Mechanism for Body-Size and -Shape Misperception. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2019; 15:133-149. [PMID: 31725353 DOI: 10.1177/1745691619869331] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
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.
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Affiliation(s)
- Kevin R Brooks
- Department of Psychology, Macquarie University.,Perception in Action Research Centre, Macquarie University
| | - Jonathan Mond
- Centre for Rural Health, University of Tasmania.,Translational Health Research Institute, School of Medicine, Western Sydney University
| | - Deborah Mitchison
- Department of Psychology, Macquarie University.,Translational Health Research Institute, School of Medicine, Western Sydney University.,Centre for Emotional Health, Department of Psychology, Macquarie University
| | - Richard J Stevenson
- Department of Psychology, Macquarie University.,Perception in Action Research Centre, Macquarie University
| | | | - Ian D Stephen
- Department of Psychology, Macquarie University.,Perception in Action Research Centre, Macquarie University
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18
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Jones AR, Tovée MJ, Cutler LR, Parkinson KN, Ells LJ, Araujo-Soares V, Pearce MS, Mann KD, Scott D, Harris JM, Adamson AJ. Development of the MapMe intervention body image scales of known weight status for 4-5 and 10-11 year old children. J Public Health (Oxf) 2019; 40:582-590. [PMID: 29190364 PMCID: PMC6266708 DOI: 10.1093/pubmed/fdx129] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 09/18/2017] [Indexed: 11/12/2022] Open
Abstract
Background Parents tend to visually assess children to determine their weight status and typically underestimate child body size. A visual tool may aid parents to more accurately assess child weight status and so support strategies to reduce childhood overweight. Body image scales (BIS) are visual images of people ranging from underweight to overweight but none exist for children based on UK criteria. Our aim was to develop sex- and age-specific BIS for children, based on British growth reference (UK90) criteria. Methods BIS were developed using 3D surface body scans of children, their associated weight status using UK90 criteria from height and weight measurements, and qualitative work with parents and health professionals. Results Height, weight and 3D body scans were collected (211: 4–5 years; 177: 10–11 years). Overall, 12 qualitative sessions were held with 37 participants. Four BIS (4–5-year-old girls and boys, 10–11-year-old girls and boys) were developed. Conclusions This study has created the first sex- and age-specific BIS, based on UK90 criteria. The BIS have potential for use in child overweight prevention and management strategies, and in future research. This study also provides a protocol for the development of further BIS appropriate to other age groups and ethnicities.
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Affiliation(s)
- A R Jones
- Institute of Health & Society, Human Nutrition Research Centre, Newcastle University, Newcastle upon Tyne, UK
| | - M J Tovée
- School of Psychology, University of Lincoln, Lincoln, UK.,Institute of Health & Society, Newcastle University, Newcastle upon Tyne, UK
| | - L R Cutler
- Institute of Health & Society, Human Nutrition Research Centre, Newcastle University, Newcastle upon Tyne, UK
| | - K N Parkinson
- Institute of Health & Society, Human Nutrition Research Centre, Newcastle University, Newcastle upon Tyne, UK
| | - L J Ells
- School of Health and Social Care, Health and Social Care Institute, Teesside University, Middlesbrough, UK
| | - V Araujo-Soares
- Institute of Health & Society, Newcastle University, Newcastle upon Tyne, UK
| | - M S Pearce
- Institute of Health & Society, Newcastle University, Newcastle upon Tyne, UK
| | - K D Mann
- Institute of Health & Society, Newcastle University, Newcastle upon Tyne, UK
| | - D Scott
- Department of Public Health and Wellbeing, Northumbria University, Newcastle upon Tyne, UK
| | - J M Harris
- School of Psychology and Neuroscience. University of St Andrews, Fife, UK
| | - A J Adamson
- Institute of Health & Society, Human Nutrition Research Centre, Newcastle University, Newcastle upon Tyne, UK
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19
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Alexi J, Dommisse K, Cleary D, Palermo R, Kloth N, Bell J. An Assessment of Computer-Generated Stimuli for Use in Studies of Body Size Estimation and Bias. Front Psychol 2019; 10:2390. [PMID: 31695661 PMCID: PMC6817789 DOI: 10.3389/fpsyg.2019.02390] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 10/07/2019] [Indexed: 12/20/2022] Open
Abstract
Inaccurate body size judgments are associated with body image disturbances, a clinical feature of many eating disorders. Accordingly, body-related stimuli have become increasingly important in the study of estimation inaccuracies and body image disturbances. Technological advancements in the last decade have led to an increased use of computer-generated (CG) body stimuli in body image research. However, recent face perception research has suggested that CG face stimuli are not recognized as readily and may not fully tap facial processing mechanisms. The current study assessed the effectiveness of using CG stimuli in an established body size estimation task (the “bodyline” task). Specifically, we examined whether employing CG body stimuli alters body size judgments and associated estimation biases. One hundred and six 17- to 25-year-old females completed the CG bodyline task, which involved estimating the size of full-length CG body stimuli along a visual analogue scale. Our results show that perception of body size for CG stimuli was non-linear. Participants struggled to discriminate between extreme bodies sizes and overestimated the size change between near to average bodies. Furthermore, one of our measured size estimation biases was larger for CG stimuli. Our collective findings suggest using caution when employing CG stimuli in experimental research on body perception.
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Affiliation(s)
- Joanna Alexi
- School of Psychological Science, University of Western Australia, Perth, WA, Australia
| | - Kendra Dommisse
- School of Psychological Science, University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
| | - Dominique Cleary
- School of Psychological Science, University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
| | - Romina Palermo
- School of Psychological Science, University of Western Australia, Perth, WA, Australia
| | - Nadine Kloth
- School of Psychological Science, University of Western Australia, Perth, WA, Australia
| | - Jason Bell
- School of Psychological Science, University of Western Australia, Perth, WA, Australia
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20
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Brooks KR, Baldry E, Mond J, Stevenson RJ, Mitchison D, Stephen ID. Gender and the Body Size Aftereffect: Implications for Neural Processing. Front Neurosci 2019; 13:1100. [PMID: 31680834 PMCID: PMC6813220 DOI: 10.3389/fnins.2019.01100] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 09/30/2019] [Indexed: 12/18/2022] Open
Abstract
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.
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Affiliation(s)
- Kevin R. Brooks
- Body Image and Ingestion Group, Department of Psychology, Macquarie University, Sydney, NSW, Australia
- Perception in Action Research Centre, Faculty of Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Evelyn Baldry
- Body Image and Ingestion Group, Department of Psychology, Macquarie University, Sydney, NSW, Australia
| | - Jonathan Mond
- Centre for Rural Health, University of Tasmania, Launceston, TAS, Australia
- Translational Health Research Institute, School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - Richard J. Stevenson
- Body Image and Ingestion Group, Department of Psychology, Macquarie University, Sydney, NSW, Australia
- Perception in Action Research Centre, Faculty of Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Deborah Mitchison
- Translational Health Research Institute, School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - Ian D. Stephen
- Body Image and Ingestion Group, Department of Psychology, Macquarie University, Sydney, NSW, Australia
- Perception in Action Research Centre, Faculty of Human Sciences, Macquarie University, Sydney, NSW, Australia
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21
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Alexi J, Palermo R, Rieger E, Bell J. Evidence for a perceptual mechanism relating body size misperception and eating disorder symptoms. Eat Weight Disord 2019; 24:615-621. [PMID: 30758775 DOI: 10.1007/s40519-019-00653-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Accepted: 02/04/2019] [Indexed: 12/11/2022] Open
Abstract
PURPOSE There are known and serious health risks associated with extreme body weights, including the development of eating disorders. Body size misperceptions are particularly evident in individuals with eating disorders, compared to healthy controls. The present research investigated whether serial dependence, a recently discovered bias in body size judgement, is associated with eating disorder symptomatology. We additionally examined whether this bias operates on holistic body representations or whether it works by distorting specific visual features. METHODS A correlational analysis was used to examine the association between serial dependence and eating disorder symptomatology. We used a within-subjects experimental design to investigate the holistic nature of this misperception. Participants were 63 young women, who judged the size of upright and inverted female body images using a visual analogue scale and then completed the Eating Disorder Examination-Questionnaire (EDE-Q) to assess eating disorder symptoms. RESULTS Our findings provide the first evidence of an association between serial dependence and eating disorder symptoms, with significant and positive correlations between body size misperception owing to serial dependence and EDE-Q scores, when controlling for Body Mass Index. Furthermore, we reveal that serial dependence is consistent with distortion of local visual features. CONCLUSIONS Findings are discussed in relation to the broader theories of central coherence, cognitive inflexibility, and multisensory integration difficulties, and as providing a candidate mechanism for body size misperception in an eating disorder population. LEVEL OF EVIDENCE Level 1, experimental study.
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Affiliation(s)
- Joanna Alexi
- School of Psychological Science, University of Western Australia, Crawley, WA, 6009, Australia. .,Australian Research Council, Centre of Excellence in Cognition and its Disorders, University of Western Australia, Crawley, WA, 6009, Australia.
| | - Romina Palermo
- School of Psychological Science, University of Western Australia, Crawley, WA, 6009, Australia.,Australian Research Council, Centre of Excellence in Cognition and its Disorders, University of Western Australia, Crawley, WA, 6009, Australia
| | - Elizabeth Rieger
- Research School of Psychology, Australian National University, Canberra, ACT, 0200, Australia
| | - Jason Bell
- School of Psychological Science, University of Western Australia, Crawley, WA, 6009, Australia.,Australian Research Council, Centre of Excellence in Cognition and its Disorders, University of Western Australia, Crawley, WA, 6009, Australia
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22
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Esdaile E, Hernandez E, Moores CJ, Vidgen HA. Enrolment of families with overweight children into a program aimed at reducing childhood obesity with and without a weight criterion: a natural experiment. BMC Public Health 2019; 19:756. [PMID: 31200674 PMCID: PMC6570944 DOI: 10.1186/s12889-019-6894-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/25/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Difficulties engaging families with overweight children to enrol into programs aimed at reducing childhood obesity have been well documented. During the implementation of the Parenting, Eating and Activity for Child Health Program (PEACH™) over a large geographical area (Queensland (QLD), Australia), a natural experiment developed. This experiment provided an opportunity to observe if there was a difference in enrolment for families with overweight children with a weight criterion (referred to as the period with a Targeted Eligibility Criterion (TEC)) compared to when a weight criterion was removed (the period referred to as Universal Eligibility Criterion (UEC)). We also examined the eligibility criterion's relationship with attendance, parental concern about their child's weight, estimation of overweight and obesity from parent-reported data. METHODS A secondary analysis of baseline data from 926 overweight/obese children from 817 families enrolled in PEACH™ QLD was performed. Analyses were adjusted to control for the presence of clustered data. Bivariate statistics were performed using Pearson chi-square test with the second-order Rao-Scott correction, and Mann-Whitney U-test for non-parametric continuous variables. Generalized Estimating Equations (GEE) explored the association between weight status-based eligibility criteria and enrolment of overweight children. GEE were adjusted for sex, age and socioeconomic index and stratified for weight category. RESULTS Compared to obese children, overweight children were almost twice as likely to be enrolled when the program did not have weight status-based eligibility criteria (during UEC period) (OR = 1.90 (CI 95% 1.35-2.68, p < 0.001)). Parents of overweight children enrolled during the UEC period were more likely to regard their child's weight as less of a concern than during the TEC period (UEC 67% vs. TEC 45%, p = 0.036). Children whose parent-reported data underestimated their weight category were more likely to be enrolled while the program did not have weight-related eligibility criteria OR = 2.27 (CI 1.38-3.70, p < 0.01). Program session attendance did not appear to be impacted by the changes in eligibility criteria. CONCLUSIONS The omission of weight criteria for healthy lifestyle programs is a consideration for health professionals and decision-makers alike when encouraging the enrolment of children who are overweight into healthy lifestyle programs. TRIAL REGISTRATION ACTRN12617000315314 . Retrospectively registered 28 February 2017.
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Affiliation(s)
- Emma Esdaile
- School of Exercise & Nutrition Sciences, Faculty of Health, Queensland University of Technology, Level 4, A Wing, O Block, Kelvin Grove, Brisbane, Queensland Qld 4059 Australia
| | - Emely Hernandez
- School of Exercise & Nutrition Sciences, Faculty of Health, Queensland University of Technology, Level 4, A Wing, O Block, Kelvin Grove, Brisbane, Queensland Qld 4059 Australia
| | - Carly Jane Moores
- Nutrition and Dietetics, College of Nursing and Health Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia 5001 Australia
| | - Helen Anna Vidgen
- School of Exercise & Nutrition Sciences, Faculty of Health, Queensland University of Technology, Level 4, A Wing, O Block, Kelvin Grove, Brisbane, Queensland Qld 4059 Australia
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23
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Gledhill LJ, George HR, Tovée MJ. Perceptual Not Attitudinal Factors Predict the Accuracy of Estimating Other Women's Bodies in Both Women With Anorexia Nervosa and Controls. Front Psychol 2019; 10:997. [PMID: 31143143 PMCID: PMC6520613 DOI: 10.3389/fpsyg.2019.00997] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 04/15/2019] [Indexed: 12/17/2022] Open
Abstract
Disturbance in how one's body shape and size is experienced, usually including over-estimation of one's own body size, is a core feature of the diagnostic criteria of anorexia nervosa (AN). Is this over-estimation specific to women with AN's judgments of their own body? Or is it just a general feature of their judgments about all bodies? If the latter, it would be consistent with a general error in the perception of body size potentially linked to the use of a different set of visual cues for judging body size. If the former, then this suggests that the over-estimation of own body size has a strong attitudinal component and may be part of the psycho-pathology of their condition. To test this hypothesis, 20 women with AN and 80 control observers estimated the body size of 46 women. The results show a strong effect of perceptual factors in estimating body size for both controls and women with AN. This result is consistent with size over-estimation of own body in AN having a strong attitudinal basis and being a core feature of the psycho-pathology of the condition.
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Affiliation(s)
- Lucinda J. Gledhill
- Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, United Kingdom
| | - Hannah R. George
- Deaf Children, Young People and Family Service (National Deaf CAMHS), York, United Kingdom
| | - Martin J. Tovée
- School of Psychology, University of Lincoln, Lincoln, United Kingdom
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24
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Wells M, Goldstein LN. An algorithm to improve the accuracy of emergency weight estimation in obese children. Pan Afr Med J 2018; 31:90. [PMID: 31011391 PMCID: PMC6461967 DOI: 10.11604/pamj.2018.31.90.13821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 09/25/2018] [Indexed: 11/23/2022] Open
Abstract
Introduction During medical emergencies in children, accurate and appropriate weight estimations may ultimately influence the outcome by facilitating the delivery of safe and effective doses of medications. Children at the extremes of habitus, especially obese children, are more at risk of an inaccurate weight estimation and therefore may be more at risk of medication errors. The objective was therefore to develop an algorithm to guide accurate emergency weight estimation in obese children. Methods Relevant medical evidence was reviewed regarding weight estimation and its role and timing in the resuscitation of obese children. This was used as the basis for a weight-estimation algorithm. Results There was limited evidence regarding the way the weight-estimation systems should be used in obese children other than that the dual length- and habitus-based systems were the most accurate. The methods included in the algorithm were the Broselow tape, the Mercy method, parental estimates, the paediatric advanced weight prediction in the emergency room/ eXtra Length-eXtra Large (PAWPER XL) tape and the Traub-Johnson formula. The algorithm recognised several ways in which weight estimation could be tailored to the clinical scenario to estimate both ideal and total body weight. Conclusion Weight-estimation in obese children must be conducted appropriately to avoid medication errors. This algorithm provides a framework to achieve this.
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Affiliation(s)
- Mike Wells
- Division of Emergency Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Lara Nicole Goldstein
- Division of Emergency Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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25
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Mölbert SC, Thaler A, Mohler BJ, Streuber S, Romero J, Black MJ, Zipfel S, Karnath HO, Giel KE. Assessing body image in anorexia nervosa using biometric self-avatars in virtual reality: Attitudinal components rather than visual body size estimation are distorted. Psychol Med 2018; 48:642-653. [PMID: 28745268 PMCID: PMC5964466 DOI: 10.1017/s0033291717002008] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 06/20/2017] [Accepted: 06/21/2017] [Indexed: 12/01/2022]
Abstract
BACKGROUND Body image disturbance (BID) is a core symptom of anorexia nervosa (AN), but as yet distinctive features of BID are unknown. The present study aimed at disentangling perceptual and attitudinal components of BID in AN. METHODS We investigated n = 24 women with AN and n = 24 controls. Based on a three-dimensional (3D) body scan, we created realistic virtual 3D bodies (avatars) for each participant that were varied through a range of ±20% of the participants' weights. Avatars were presented in a virtual reality mirror scenario. Using different psychophysical tasks, participants identified and adjusted their actual and their desired body weight. To test for general perceptual biases in estimating body weight, a second experiment investigated perception of weight and shape matched avatars with another identity. RESULTS Women with AN and controls underestimated their weight, with a trend that women with AN underestimated more. The average desired body of controls had normal weight while the average desired weight of women with AN corresponded to extreme AN (DSM-5). Correlation analyses revealed that desired body weight, but not accuracy of weight estimation, was associated with eating disorder symptoms. In the second experiment, both groups estimated accurately while the most attractive body was similar to Experiment 1. CONCLUSIONS Our results contradict the widespread assumption that patients with AN overestimate their body weight due to visual distortions. Rather, they illustrate that BID might be driven by distorted attitudes with regard to the desired body. Clinical interventions should aim at helping patients with AN to change their desired weight.
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Affiliation(s)
- S. C. Mölbert
- Department of Psychosomatic Medicine and
Psychotherapy, Medical University Hospital
Tübingen, Tübingen, Germany
- Max Planck Institute for Biological
Cybernetics, Tübingen, Germany
- Graduate Training Centre of Neuroscience,
International Max Planck Research School, Universität Tübingen,
Tübingen, Germany
| | - A. Thaler
- Max Planck Institute for Biological
Cybernetics, Tübingen, Germany
- Graduate Training Centre of Neuroscience,
International Max Planck Research School, Universität Tübingen,
Tübingen, Germany
| | - B. J. Mohler
- Max Planck Institute for Biological
Cybernetics, Tübingen, Germany
| | - S. Streuber
- École Polytechnique Fédérale de Lausanne, Brain
Mind Institute, Lausanne,
Switzerland
| | - J. Romero
- Max Planck Institute for Intelligent
Systems, Tübingen, Germany
| | - M. J. Black
- Max Planck Institute for Intelligent
Systems, Tübingen, Germany
| | - S. Zipfel
- Department of Psychosomatic Medicine and
Psychotherapy, Medical University Hospital
Tübingen, Tübingen, Germany
| | - H.-O. Karnath
- Division of Neuropsychology,
Center of Neurology, Hertie-Institute for Clinical Brain Research, University
of Tübingen, Tübingen, Germany
| | - K. E. Giel
- Department of Psychosomatic Medicine and
Psychotherapy, Medical University Hospital
Tübingen, Tübingen, Germany
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26
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Cornelissen PL, Cornelissen KK, Groves V, McCarty K, Tovée MJ. View-dependent accuracy in body mass judgements of female bodies. Body Image 2018; 24:116-123. [PMID: 29414144 DOI: 10.1016/j.bodyim.2017.12.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 12/20/2017] [Accepted: 12/20/2017] [Indexed: 11/17/2022]
Abstract
A fundamental issue in testing body image perception is how to present the test stimuli. Previous studies have almost exclusively used images of bodies viewed in front-view, but this potentially obscures key visual cues used to judge adiposity reducing the ability to make accurate judgements. A potential solution is to use a three-quarter view, which combines visual cues to body fat that can be observed in front and profile. To test this hypothesis, 20 female observers completed a 2-alternative forced choice paradigm to determine the smallest difference in body fat detectable in female bodies in front, three-quarter, and profile view. There was a significant advantage for three-quarter and profile relative to front-view. Discrimination accuracy is predicted by the saliency of stomach depth, suggesting that this is a key visual cue used to judge body mass. In future, bodies should ideally be presented in three-quarter to accurately assess body size discrimination.
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Affiliation(s)
- Piers L Cornelissen
- Department of Psychology, Faculty of Health & Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK
| | - Katri K Cornelissen
- Department of Psychology, Faculty of Health & Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK
| | - Victoria Groves
- Department of Psychology, Faculty of Health & Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK
| | - Kristofor McCarty
- Department of Psychology, Faculty of Health & Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, UK
| | - Martin J Tovée
- School of Psychology, College of Social Science, University of Lincoln, Lincolnshire, LN6 7TS, UK.
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27
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Body size estimation of self and others in females varying in BMI. PLoS One 2018; 13:e0192152. [PMID: 29425218 PMCID: PMC5806871 DOI: 10.1371/journal.pone.0192152] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 01/17/2018] [Indexed: 11/23/2022] Open
Abstract
Previous literature suggests that a disturbed ability to accurately identify own body size may contribute to overweight. Here, we investigated the influence of personal body size, indexed by body mass index (BMI), on body size estimation in a non-clinical population of females varying in BMI. We attempted to disentangle general biases in body size estimates and attitudinal influences by manipulating whether participants believed the body stimuli (personalized avatars with realistic weight variations) represented their own body or that of another person. Our results show that the accuracy of own body size estimation is predicted by personal BMI, such that participants with lower BMI underestimated their body size and participants with higher BMI overestimated their body size. Further, participants with higher BMI were less likely to notice the same percentage of weight gain than participants with lower BMI. Importantly, these results were only apparent when participants were judging a virtual body that was their own identity (Experiment 1), but not when they estimated the size of a body with another identity and the same underlying body shape (Experiment 2a). The different influences of BMI on accuracy of body size estimation and sensitivity to weight change for self and other identity suggests that effects of BMI on visual body size estimation are self-specific and not generalizable to other bodies.
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28
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Oldham M, Robinson E. Visual body size norms and the under-detection of overweight and obesity. Obes Sci Pract 2018; 4:29-40. [PMID: 29479462 PMCID: PMC5818735 DOI: 10.1002/osp4.143] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 11/20/2017] [Accepted: 11/21/2017] [Indexed: 02/01/2023] Open
Abstract
Objectives The weight status of men with overweight and obesity tends to be visually underestimated, but visual recognition of female overweight and obesity has not been formally examined. The aims of the present studies were to test whether people can accurately recognize both male and female overweight and obesity and to examine a visual norm-based explanation for why weight status is underestimated. Methods The present studies examine whether both male and female overweight and obesity are visually underestimated (Study 1), whether body size norms predict when underestimation of weight status occurs (Study 2) and whether visual exposure to heavier body weights adjusts visual body size norms and results in underestimation of weight status (Study 3). Results The weight status of men and women with overweight and obesity was consistently visually underestimated (Study 1). Body size norms predicted underestimation of weight status (Study 2) and in part explained why visual exposure to heavier body weights caused underestimation of overweight (Study 3). Conclusions The under-detection of overweight and obesity may have been in part caused by exposure to larger body sizes resulting in an upwards shift in the range of body sizes that are perceived as being visually 'normal'.
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Affiliation(s)
- M. Oldham
- Psychological SciencesUniversity of LiverpoolLiverpoolUK
| | - E. Robinson
- Psychological SciencesUniversity of LiverpoolLiverpoolUK
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29
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Visual attention mediates the relationship between body satisfaction and susceptibility to the body size adaptation effect. PLoS One 2018; 13:e0189855. [PMID: 29385137 PMCID: PMC5791942 DOI: 10.1371/journal.pone.0189855] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 12/04/2017] [Indexed: 12/16/2022] Open
Abstract
Body size misperception–the belief that one is larger or smaller than reality–affects a large and growing segment of the population. Recently, studies have shown that exposure to extreme body stimuli results in a shift in the point of subjective normality, suggesting that visual adaptation may be a mechanism by which body size misperception occurs. Yet, despite being exposed to a similar set of bodies, some individuals within a given geographical area will develop body size misperception and others will not. The reason for these individual difference is currently unknown. One possible explanation stems from the observation that women with lower levels of body satisfaction have been found to pay more attention to images of thin bodies. However, while attention has been shown to enhance visual adaptation effects in low (e.g. rotational and linear motion) and high level stimuli (e.g., facial gender), it is not known whether this effect exists in visual adaptation to body size. Here, we test the hypothesis that there is an indirect effect of body satisfaction on the direction and magnitude of the body fat adaptation effect, mediated via visual attention (i.e., selectively attending to images of thin over fat bodies or vice versa). Significant mediation effects were found in both men and women, suggesting that observers’ level of body satisfaction may influence selective visual attention to thin or fat bodies, which in turn influences the magnitude and direction of visual adaptation to body size. This may provide a potential mechanism by which some individuals develop body size misperception–a risk factor for eating disorders, compulsive exercise behaviour and steroid abuse–while others do not.
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30
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Abstract
Body size is a salient marker of physical health, with extremes implicated in various mental and physical health issues. It is therefore important to understand the mechanisms of perception of body size of self and others. We report a novel technique we term the bodyline, based on the numberline technique in numerosity studies. One hundred and three young women judged the size of sequentially presented female body images by positioning a marker on a line, delineated with images of extreme sizes. Participants performed this task easily and well, with average standard deviations less than 6% of the total scale. Critically, judgments of size were biased towards the previously viewed body, demonstrating that serial dependencies occur in the judgment of body size. The magnitude of serial dependence was well predicted by a simple Kalman-filter ideal-observer model, suggesting that serial dependence occurs in an optimal, adaptive way to improve performance in size judgments.
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31
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Cornelissen KK, McCarty K, Cornelissen PL, Tovée MJ. Body size estimation in women with anorexia nervosa and healthy controls using 3D avatars. Sci Rep 2017; 7:15773. [PMID: 29150646 PMCID: PMC5693901 DOI: 10.1038/s41598-017-15339-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 10/16/2017] [Indexed: 01/22/2023] Open
Abstract
A core feature of anorexia nervosa is an over-estimation of body size. However, quantifying this over-estimation has been problematic as existing methodologies introduce a series of artefacts and inaccuracies in the stimuli used for judgements of body size. To overcome these problems, we have: (i) taken 3D scans of 15 women who have symptoms of anorexia (referred to henceforth as anorexia spectrum disorders, ANSD) and 15 healthy control women, (ii) used a 3D modelling package to build avatars from the scans, (iii) manipulated the body shapes of these avatars to reflect biometrically accurate, continuous changes in body mass index (BMI), (iv) used these personalized avatars as stimuli to allow the women to estimate their body size. The results show that women who are currently receiving treatment for ANSD show an over-estimation of body size which rapidly increases as their own BMI increases. By contrast, the women acting as healthy controls can accurately estimate their body size irrespective of their own BMI. This study demonstrates the viability of combining 3D scanning and CGI techniques to create personalised realistic avatars of individual patients to directly assess their body image perception.
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Affiliation(s)
- Katri K Cornelissen
- Department of Psychology, Northumbria University, Newcastle Upon Tyne, NE1 8ST, United Kingdom
| | - Kristofor McCarty
- Department of Psychology, Northumbria University, Newcastle Upon Tyne, NE1 8ST, United Kingdom
| | - Piers L Cornelissen
- Department of Psychology, Northumbria University, Newcastle Upon Tyne, NE1 8ST, United Kingdom
| | - Martin J Tovée
- School of Psychology, Lincoln University, Lincoln, LN6 7TS, United Kingdom.
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32
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Robinson E. Overweight but unseen: a review of the underestimation of weight status and a visual normalization theory. Obes Rev 2017; 18:1200-1209. [PMID: 28730613 PMCID: PMC5601193 DOI: 10.1111/obr.12570] [Citation(s) in RCA: 127] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 04/28/2017] [Accepted: 05/09/2017] [Indexed: 11/26/2022]
Abstract
Although overweight and obesity are widespread across most of the developed world, a considerable body of research has now accumulated, which suggests that adiposity often goes undetected. A substantial proportion of individuals with overweight or obesity do not identify they are overweight, and large numbers of parents of children with overweight or obesity fail to identify their child as being overweight. Lay people and medical practitioners are also now poor at identifying overweight and obesity in others. A visual normalization theory of the under-detection of overweight and obesity is proposed. This theory is based on the notion that weight status is judged relative to visual body size norms. Because larger body sizes are now common, this has caused a recalibration to the range of body sizes that are perceived as being 'normal' and increased the visual threshold for what constitutes 'overweight'. Evidence is reviewed that indicates this process has played a significant role in the under-detection of overweight and obesity. The public health relevance of the under-detection of overweight and obesity is also discussed.
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Affiliation(s)
- E. Robinson
- Department of Psychological SciencesUniversity of LiverpoolLiverpoolUK
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33
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A systematic review and meta-analysis of the accuracy of weight estimation systems used in paediatric emergency care in developing countries. Afr J Emerg Med 2017; 7:S36-S54. [PMID: 30505673 PMCID: PMC6246873 DOI: 10.1016/j.afjem.2017.06.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 06/13/2017] [Accepted: 06/29/2017] [Indexed: 11/23/2022] Open
Abstract
Introduction When weight cannot be measured during the management of medical emergencies in children, a convenient, quick and accurate method of weight estimation is required, as many drug doses and other interventions are based on body weight. Many weight estimation methodologies in current use have been shown to be inaccurate, especially in low- and middle-income countries with a high prevalence of underweight children. This meta-analysis evaluated the accuracy of weight estimation systems in children from studies from low- and middle-income countries. Methods Articles from low- and middle-income countries were screened for inclusion to evaluate and compare the accuracy of existing systems and the newer dual length- and habitus-based methods, using standard meta-analysis techniques. Results The 2D systems and parental estimates performed best overall. The PAWPER tape, parental estimates, the Wozniak method and the Mercy method were the most accurate systems with percentage of weight estimates within 10% of actual weight (PW10) accuracies of 86.9%, 80.4%, 72.1% and 71.4% respectively. The Broselow tape (PW10 47.1%) achieved a moderate accuracy and age-based estimates a very low accuracy (PW10 11.8–47.5%). Conclusions The PAWPER tape, the Wozniak method and the Mercy method achieved an acceptable level of accuracy in studies from low- and middle-income countries and should preferentially be used and further advanced for clinical emergency medicine practice. Parental estimates may be considered if the regular caregiver of the child is present and a recent measured weight is known. The Broselow tape and age-based formulas should be abandoned in low- and middle-income country populations as they are potentially dangerously inaccurate.
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34
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Gledhill LJ, Cornelissen KK, Cornelissen PL, Penton-Voak IS, Munafò MR, Tovée MJ. An interactive training programme to treat body image disturbance. Br J Health Psychol 2016; 22:60-76. [PMID: 27813208 PMCID: PMC5248599 DOI: 10.1111/bjhp.12217] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/24/2016] [Indexed: 12/02/2022]
Abstract
Objectives Anorexia nervosa (AN) is a life‐threatening mental health condition. A core feature is a disturbance of body image, such that sufferers see themselves as fatter than they actually are. Design We tested the effectiveness of a novel training programme to recalibrate our participants’ perception of body size. Methods In a novel adaptation of a cognitive bias training programme, participants judged the body size of a series of female bodies and were given feedback to improve their accuracy over four daily training sessions. In Study 1, we recruited young women with high concerns about their body size for a randomized controlled study. In Study 2, we then applied the training programme to a case series of women with atypical AN. Results In Study 1, the training programme significantly improved the body size judgements of women with high body concerns compared to controls. We also found evidence of improved body image and reduced eating concerns in this group. In Study 2, the programme again recalibrated the body size judgements of women with atypical AN. We also saw evidence of a clinically meaningful reduction in their body size and eating‐disordered concerns. Conclusions This training has the potential to be a valuable treatment used together with more traditional talking therapies. Statement of contribution What is already known on this subject? A core feature of anorexia nervosa (AN) is an overestimation of body size; sufferers believe themselves to be larger than they are in reality. This study shows that an individual's perceptual boundary between what they classify as a fat versus a thin body is not immutable; it can be changed through a cognitive bias training programme. What does this study add? This means that body size overestimation may now be treatable. Critically, as well as improving the accuracy of body size judgements, we also found a clinically significant improvement in participants’ eating‐disordered concerns. This demonstrates that a targeted behavioural training regime can change body perception, and the central role that body overestimation has in eating‐disordered beliefs.
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Affiliation(s)
- Lucinda J Gledhill
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | | | | | | | - Marcus R Munafò
- School of Experimental Psychology, University of Bristol, UK.,MRC Integrative Epidemiology Unit at the University of Bristol, UK
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35
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Brierley ME, Brooks KR, Mond J, Stevenson RJ, Stephen ID. The Body and the Beautiful: Health, Attractiveness and Body Composition in Men's and Women's Bodies. PLoS One 2016; 11:e0156722. [PMID: 27257677 PMCID: PMC4892674 DOI: 10.1371/journal.pone.0156722] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 05/18/2016] [Indexed: 12/25/2022] Open
Abstract
The dominant evolutionary theory of physical attraction posits that attractiveness reflects physiological health, and attraction is a mechanism for identifying a healthy mate. Previous studies have found that perceptions of the healthiest body mass index (weight scaled for height; BMI) for women are close to healthy BMI guidelines, while the most attractive BMI is significantly lower, possibly pointing to an influence of sociocultural factors in determining attractive BMI. However, less is known about ideal body size for men. Further, research has not addressed the role of body fat and muscle, which have distinct relationships with health and are conflated in BMI, in determining perceived health and attractiveness. Here, we hypothesised that, if attractiveness reflects physiological health, the most attractive and healthy appearing body composition should be in line with physiologically healthy body composition. Thirty female and 33 male observers were instructed to manipulate 15 female and 15 male body images in terms of their fat and muscle to optimise perceived health and, separately, attractiveness. Observers were unaware that they were manipulating the muscle and fat content of bodies. The most attractive apparent fat mass for female bodies was significantly lower than the healthiest appearing fat mass (and was lower than the physiologically healthy range), with no significant difference for muscle mass. The optimal fat and muscle mass for men's bodies was in line with the healthy range. Male observers preferred a significantly lower overall male body mass than did female observers. While the body fat and muscle associated with healthy and attractive appearance is broadly in line with physiologically healthy values, deviations from this pattern suggest that future research should examine a possible role for internalization of body ideals in influencing perceptions of attractive body composition, particularly in women.
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Affiliation(s)
| | - Kevin R. Brooks
- Department of Psychology, Macquarie University, Sydney, Australia
- Perception in Action Research Centre (PARC), Faculty of Human Sciences, Macquarie University, Sydney, Australia
| | - Jonathan Mond
- Department of Psychology, Macquarie University, Sydney, Australia
| | - Richard J. Stevenson
- Department of Psychology, Macquarie University, Sydney, Australia
- Perception in Action Research Centre (PARC), Faculty of Human Sciences, Macquarie University, Sydney, Australia
| | - Ian D. Stephen
- Department of Psychology, Macquarie University, Sydney, Australia
- ARC Centre of Excellence in Cognition and its Disorders, Sydney, Australia
- Perception in Action Research Centre (PARC), Faculty of Human Sciences, Macquarie University, Sydney, Australia
- * E-mail:
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36
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Cornelissen KK, Cornelissen PL, Hancock PJB, Tovée MJ. Fixation patterns, not clinical diagnosis, predict body size over-estimation in eating disordered women and healthy controls. Int J Eat Disord 2016; 49:507-18. [PMID: 26996142 PMCID: PMC5071724 DOI: 10.1002/eat.22505] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 12/11/2015] [Accepted: 12/11/2015] [Indexed: 11/08/2022]
Abstract
OBJECTIVE A core feature of anorexia nervosa (AN) is an over-estimation of body size. Women with AN have a different pattern of eye-movements when judging bodies, but it is unclear whether this is specific to their diagnosis or whether it is found in anyone over-estimating body size. METHOD To address this question, we compared the eye movement patterns from three participant groups while they carried out a body size estimation task: (i) 20 women with recovering/recovered anorexia (rAN) who had concerns about body shape and weight and who over-estimated body size, (ii) 20 healthy controls who had normative levels of concern about body shape and who estimated body size accurately (iii) 20 healthy controls who had normative levels of concern about body shape but who did over-estimate body size. RESULTS Comparisons between the three groups showed that: (i) accurate body size estimators tended to look more in the waist region, and this was independent of clinical diagnosis; (ii) there is a pattern of looking at images of bodies, particularly viewing the upper parts of the torso and face, which is specific to participants with rAN but which is independent of accuracy in body size estimation. DISCUSSION Since the over-estimating controls did not share the same body image concerns that women with rAN report, their over-estimation cannot be explained by attitudinal concerns about body shape and weight. These results suggest that a distributed fixation pattern is associated with over-estimation of body size and should be addressed in treatment programs. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:507-518).
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Affiliation(s)
| | | | | | - Martin J. Tovée
- Institute of Neuroscience, Newcastle UniversityTyne and WearUnited Kingdom
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