1. Langlois, Ritter, Roggman, and Vaughn (1991)
Facial Diversity and Infant Preferences for Attractive Faces
Developmental ψ

2. Attractiveness Nature vs. Nurture
Pretty is as pretty does.
Beauty is only skin deep.
Never judge a book by its cover.

3. Attractiveness Nurture?
Are preferences for attractiveness culturally transmitted?
Lengthened necks
Bound feet
Painted skin
Dyed hair
Flattened or enlarged breasts
Fat
Thin

4. Attractiveness Nurture?

5. Attractiveness Nature?
“Beautiful faces and bodies worldwide are generally ones that look youthful, healthy, symmetrical, "average" in the sense that we prefer features– noses, legs, physiques–  that are neither too large nor too small” David G. Myers in Psychology.

6. Attractiveness Nature
These images were created by morphing together the features of many women to come up with the "average" face.

7. Langlois et al. 3 tests of attractiveness
White adults (male♂ & female♀)
Black female♀ adults
3-months old infants (♂ & ♀)
Previous study:
White female♀

8. Method Laboratory experiment IV? What was manipulated?
DV? What was measured?

9. Method 8 x 2 faces were projected on to a screen
½ attractive – ½ unattractive (Likert scale)
Child on parents´s lap
Parent wore occluded glasses.
Light & buzz: 10s / trial
Neutral expressions, clothing masked
Controlled R/L presentation
Infants given 5-10-min break after 8 trials to lessen fatigue

10. Method
Operational definition of attractive: The slides’ faces were rated for attractiveness by at least 40 undergraduate men & women using a 5-point Likert-type scale (rating scale)
Final faces selected:
Facial expression, hair length, hair color were equally distributed across attractiveness conditions
All male faces clean-shaven
Clothing cues masked
Faces were posed with neutral expressions
Maternal attractiveness was evaluated in studies 1 and 2. (Why not in study 3?)

11. Method Standard visual preference technique
Infant seated on parent's lap; parent wore occluded glasses. Why?
A light and a buzzing noise
A trial began when the infant first looked at one of the slides
When the infant looked at the center of the screen, the next pair of slides was displayed.
Each trial lasted for 10 s.
Screen brightness consistent throughout

12. Method
Direction & duration of looks recorded on the keyboard of a laboratory computer that functioned as an event recorder
Using the televised image of the infant to observe visual fixation ensured that the experimenter could not see the displayed slides & was therefore blind to the attractiveness level of the slides the infant was observing
Reliability of the visual-fixation scoring obtained by having each experimenter score randomly selected videotaped sessions periodically throughout data collection

13. White adults (male♂ & female♀)
Study 1

14. Study 1: Aim
To replicate their previous results with adult female facial stimuli
To extend the results to male facial stimuli
To investigate whether the manner in which male and female faces are presented influences infant preferences

15. Study 1: Sample
60-6 month old infants
53 of them were white

16. Study 1: Method
Each infant saw color slides of 16 adult Caucasian women & 16 Caucasian adult men
Half of the slides of each sex depicted attractive faces, the other half unattractive faces

17. Study 1: Method The stimuli were presented in two sets of 16 slides
Each set divided into 8 trial blocks of 2 slides each
Control for infant side biases
Slides paired so that infants viewed only pairs of women or pairs of men
Alternating condition, the infants observed alternating pairs of males and females.
Grouped condition, infants saw all the women's slides together & all the men's slides together

18. Study 1: Method
Order of set presentation, order of slide pair presentation within sets (within the constraints of the set), & order of slide pairing randomized across subjects so that a particular slide of an attractive face could be paired with any slide of an unattractive face of the same sex

19. Study 1: Results ♂ face ♀ face M SD ♂ Infant 7.95 1.45 7.36 1.31
7.69
1.35
7.81
1.33
♂ Infants look longer at ♂ faces p ˂ 0.01
♀ Infants look longer at ♀ faces p not significantly
M: Media SD: Standard deviation

20. Study 1: Results
Infants looked longer at the attractive faces than the unattractive faces
Infant preferences for attractive faces were evident for both adult male & adult female faces
Condition of presentation was not significant
Boys looked longer at male faces
Girls also preferred same sex faces but the finding was not statistically significant
Mother’s attractiveness did not make a difference (Why do this?)

21. Black adults female♀
Study 2

22. Study 2: Aim To extend the findings to non-white faces
Infants were shown faces of Black adult women. The faces were rated for attractiveness by both Black and Caucasian adult judges.

23. Study 2: Method Sample Presentation 40-6 month old infants (36 white)
Black adult female faces
Rest of procedure same as study 1

24. Study 2: Results
Infants looked longer at the attractive faces than the unattractive faces
Mother’s attractiveness did not make a difference

25. 3-months old infants (male♂ & female♀)
Study 3

26. Study 3 Aim Sample Presentation To extend the findings to infant faces
39-6 month old infants (36 white)
Presentation
3 months old baby faces
Rest of procedure as in study 1

27. Study 3: Results
Infants looked longer at the attractive faces than the unattractive faces

28. Results – fixation times
High attractiveness
Low attractiveness M SD
White ♂♀
Infants look longer at attractive faces p=0.03
Black ♀
Infants look longer at attractive faces p˂0.05
Babies ♂♀
Infants look longer at attractive faces p˂0.04

29. Explanation
“Ethnically diverse faces possess both distinct and similar, perhaps even universal, structural features.”
Beauty is (in some part) nature NOT nurture

30. Discussion
Beautiful faces are prototypical: an original form serving as a basis or standard for other forms
Why might prototypical faces be evolutionarily adaptive?
Individuals closer to the mean might be less likely to have genetic mutations?

31. Averageness
An average face has mathematically average trait values for a population
Faces that are high in averageness are low in distinctiveness and are therefore prototypical
Several theorists have proposed that average traits reflect developmental stability

32. Prototypes
Averaged faces become more attractive as more faces are added (Langlois & Roggman, 1990)

33. Evaluation Infant preferences were Validity Consistent, but…
Only for unfamiliar faces…
Why? Familiar caregivers: ↑attachment
Validity
High experimental ☺
High or low external (ecological)? - all types of faces? / too many white participants?

34. Evaluation Visual preferences paradigm is comparative, not absolute
In other study (Langlois et al. 1987), however, 6-month old infants prefered attractive faces when presented alone
→ visual preference paradigm din´t biased the results

35. Vocabulary alert Cultural transmission Evolutionary preferences
Statistical significance
Likert-type scale
Prototype
External validity
Experimental validity
Attractiveness
Nature
Nurture
Visual preferences

36. What do 100 people from London look like?

37. What does the face of 7 billion look like?