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The Perception of Body Image in

Disordered Eating

Prof Martin Tovée

School of Psychology

University of Lincoln

• DSM 5, criterion 3: Disturbance in the way one's body

weight or shape is experienced, undue influence of body

shape and weight on self-evaluation, or persistent lack of

recognition of the seriousness of the current low body

weight.

• Two modalities of body-image dysfunction have been

distinguished:

1) Perceptual body-size distortion

2) Attitudinal / cognitive-evaluative dissatisfaction

BODY IMAGE DISTORTION

Anorexia Nervosa

Person has difficulty accurately

gauging body size. Eating-

disordered individuals estimate

their size as larger than is

objectively true.

Perceptual distortion

Patient may estimate size

accurately, but is extremely

dissatisfied with size, shape, or

some other aspect of body

appearance.

Attitudinal distortion

+

Time

Button press:

larger or smaller

than me?

Time

Two Alternative Forced Choice (2AFC)

+

Button press:

larger or smaller

than me?

Estimate Point of Subjective Equality

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Estimate Point of Subjective Equality

PSE B PSE A PSE C

Estimate Point of Subjective Equality

PSE B PSE A PSE C

Estimate Point of Subjective Equality

PSE B PSE A PSE C

Estimate Sensitivity: Difference Limen

Difference Limen (DL)

PSE B PSE A PSE C DL A

Difference Limen (DL)

Estimate Sensitivity: Difference Limen

PSE B PSE A PSE C DL A

DL B

ANSD (n=42) Control(n=100)

M SD M SD p

Participant characteristics

Age (years) 23.80 6.05 24.02 8.91 .99

BMI (weight/height2) 20.89 2.84 24.01 5.03 <.01

Percentage body fat 25.56 6.41 31.63 5.04 <.01

Depression and self esteem

BDI 20.00 11.37 9.09 6.08 <.01

RSE 14.00 5.96 18.56 4.79 <.01

Eating and body shape concern

EAT 27.38 15.55 11.07 9.08 <.01

BSQ 61.10 18.63 50.08 17.33 <.01

EDEQ 3.12 1.42 2.01 1.21 <.01

EDEQ wc 3.50 1.48 2.21 1.44 <.01

EDEQ bs 4.04 1.46 2.97 1.50 <.01

Psychophysical performance

PSE (weight/height2) 22.21 4.95 23.80 5.13 .36

OE (i.e., PSE – BMI) 1.41 3.04 -0.14 2.85 .04

DL (weight/height2) 0.72 0.66 0.99 0.81 .32

Two Alternative Forced Choice (2AFC)

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Healthy Controls (n=100)

Contraction Bias Weber’s Law

Cornelissen et al., (2015) Body Image, 13:75-85.

Δ𝐼

𝐼 + 𝑎= 𝐾

Illustrated results

BMI

Actual

body sizes

Lighter Population Heavier

than average average than average

Cornelissen et al. 2015. Body Image, 13, 75-85

Illustrated results

BMI

Actual

body sizes

Control body

size estimatesn=100

Over-estimate Accurate Under-estimate

Contraction Bias (normal)

ANSD (n=42)

Cornelissen et al., (2015) Body Image, 13:75-85.

What does this mean?

BMI

Veridical

Control

Anorexic

Ideal Bodies in Europe and

the USA

Tovée et al. Lancet

1998, 352, 548

Tovée et al. Nature

1999, 399, 215-216.

10 15 20 25 30 35

0

1

2

3

4

5

6

7

Mean a

ttra

ctivenes r

ating

BMI

0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00

0

1

2

3

4

5

6

7

Mean a

ttra

ctiveness r

ating

Waist:Hip ratio

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UK vs South African

Observers

Observers

M F

A

C

n = 50

Stimuli

Tovée et al. (2006) Evolution and Human Behavior 27, 443-456.

UK vs South African

Observers

Cauc uk-uk

Afr uk-uk

Afr zu-uk

Afr zu-zu

Born

Tested

Born

Tested

Born

Tested

Born

Tested

10 15 20 25 30 35 40 45

2

4

6

8

10

Att

racti

ven

ess

BMI

?

Tovée et al. (2006) Evolution and Human Behavior 27, 443-456.

Attractiveness Ratings

Cauc UK-UK

10 15 20 25 30 35 40

1

2

3

4

5

6

7

Att

racti

ven

ess R

ati

ng

BMI

Tovée et al. (2006) Evolution and Human Behavior 27, 443-456.

Attractiveness Ratings

Cauc UK-UK

Afr Zu-Zu

10 15 20 25 30 35 40

1

2

3

4

5

6

7A

ttra

ctive

ne

ss R

atin

g

BMI

Tovée et al. (2006) Evolution and Human Behavior 27, 443-456.

Attractiveness Ratings

Afr Zu-Zu

Afr Zu-UK

10 15 20 25 30 35 40

1

2

3

4

5

6

7

Att

racti

ven

ess R

ati

ng

s

BMI

Tovée et al. (2006) Evolution and Human Behavior 27, 443-456.

Attractiveness Ratings

Afr Zu-UK

Afr UK-UK

10 15 20 25 30 35 40

1

2

3

4

5

6

7

Attra

ctive

ne

ss R

atin

g

BMI

Tovée et al. (2006) Evolution and Human Behavior 27, 443-456.

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Nicaragua

• Villages with no electricity and

no TV access

• Villages with limited electricity

and limited TV access

• Villages with electricity and full

TV access

• The government is rolling out

electricity to villages currently

with no electricity

Nicaragua Study

Two designs:

• Cross-Sectional – looking

across villages with

different levels of media

access

• Longitudinal – looking at

changes over time in

villages which are being

electrified.

Nicaragua Study

• Adult women – their

perception of their actual

and ideal body

• Adult men – their

perception of women’s

bodies and their ideal

partner

• Adolescent children –

their perception of their

actual and ideal body

Nicaragua: Cross Sectional

Rating Study

• Managua - high levels of TV (n=41)

• Square Point –no TV (n=44)

• Kakabila –limited TV (n=66)

Nicaragua

Managua

Boothroyd et al. (2016) British Journal of Psychology, 107: 752-767

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Nicaragua

Managua

Square Point

Boothroyd et al. (2016) British Journal of Psychology, 107: 752-767

Nicaragua

Managua

Square Point

Kakabila

Boothroyd et al. (2016) British Journal of Psychology, 107: 752-767

Nicaragua

Thornborrow et al. (2018). Evolution & Human Behavior, submitted

UK White Male Preference

Thornborrow et al. (2018). Evolution & Human Behavior, submitted

UK Black Male Preference

Thornborrow et al. (2018). Evolution & Human Behavior, submitted

Kakabila Male Preference

Thornborrow et al. (2018). Evolution & Human Behavior, submitted

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Square Point Male Preference

Thornborrow et al. (2018). Evolution & Human Behavior, submitted

+

Time

Respond by button

press “is the body fat

or thin”

Time

Two Alternative Forced Choice (2-

AFC)

+

Categorical Judgements of Body Size

Tovée, Edmonds & Vuong (2012) Evolution & Human Behavior, 33(2), 85-93.

Categorical Judgements of Body Size

Tovée, Edmonds & Vuong (2012) Evolution & Human Behavior, 33(2), 85-93.

Training regime

Gledhill et al. British Journal of Health Psychology 2017, 22, 60-76.

+

TimeTime

+

?

1500 – 2500 ms

150 ms

150 ms

Incorrect.

That body was thin.

Respond by button

press: thin or fat?

Inflationary feedback

Participant told ‘Correct’ or ‘Incorrect’ relative to their

Categorical Boundary + 2 BMI units

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Training regime

ANSD

(n=21)

M SD

Age (years) 27.7 7.48

BMI 19.5 3.30

BSQ 62.5 18.77

EDE-Q 3.6 1.60

Note. BMI = Body Mass Index.

BSQ = Body Shape Questionnaire.

EDE-Q = Eating Disorder Examination

Questionnaire global score.

DAY 1 Psychometric tasks

2AFC Baseline & Training

DAY 2 2AFC Baseline & Training

DAY 3 2AFC Baseline & Training

DAY 4 2AFC Baseline & Training

Psychometric tasks

DAY 7 2AFC Baseline

Psychometric tasks

DAY 30 2AFC Baseline

Psychometric tasks

Gledhill et al. British Journal of Health Psychology 2017, 22, 60-76.

Results

Gledhill et al. British Journal of Health Psychology 2017, 22, 60-76.

Future Research 3D Scanning

3D Scanning Virtual Reality

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Body size self - estimation tool

i) Input known BMI

ii) Program shows

appropriate image

representing that BMI

i) Adjust slider to match

actual / desired body size

ii) Program returns BMI of

selected image

OR

Visual feedback for motivation for

adult weight loss and weight loss

maintenance

Q: What would I look like?

Do I want that?

How can I stay

motivated to lose the

10 kg and keep it off?

A: Visualization(map shape ↔ weight)

Motivating adult weight loss and its

maintenance

Change needed in Kg or BMI

Shape you are Shape you want to be

The moving image…

The moving image…

McCarty et al. (2017) Scientific Reports 7, 42435

Relax

It’s all been a bad dream…

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Thank you for your attention

Any Questions?