1. Olfactory Cues Modulate Facial Attractiveness Dematte, Osterbauer, & Spence (2007)

2. Background Facial attractiveness has been shown to be a universal socially important cue and an important factor in our overall rating of physical attractiveness One’s appearance has also been shown to be impacted by other sensory cues, such as one’s voice and smell Past studies have shown that we tend to rate those with direct or indirect pleasant scents higher than those without scents Smell is the most primitive and provocative  We categorize it from appealing to repulsive (rarely neutral) Scents evoke emotional memories

3. Background Past research has shown:  Women look best at times of ovulation (yes, this was an actual study- stripper study- http://www.unm.edu/~gfmiller/cycle_effects_on_tips.pdf)http://www.unm.edu/~gfmiller/cycle_effects_on_tips.pdf  Women think men look best when they are ovulating Brynar (2008) study found evidence that women who take birth control pills have a tendency to interfere with one’s fondness of a mate with different genes and instead attracts them to potential mates with more similar genes  Voices have been shown to influence a person’s perceived attractiveness (English accent recently ranked #1)

4. Background Previous research did not vary olfactory cues (which Dematte does here) Numerous studies confer that women have a better sense of smell than men (sharpest at ages 20-40) Current study only presented male faces to female Ps because: -previous studies suggest that females are more sensitive to olfactory cues -suggested that females might rely more on olfactory cues for mating behaviors than males

5. Aim & Hypothesis of the Study Aim: To investigate whether the perceived attractiveness of faces is affected by olfactory cues  In particular, the study investigated whether a pleasant or unpleasant smell affects one’s judgments of facial attractiveness Hypothesis: A pleasant odour will result in a higher rating of the perceived attractiveness of the presented male faces

6. Methodology- Sample No indication of sampling methodology 16 females from the University of Oxford Age range 20-34, mean age of 26 All were naïve as to the purpose of the experiment All answered a questionnaire for control purposes:  Good general health & no colds/flu, and/or allergies  Normal sense of olfactory and visual senses  Ability to perceive odours and colors

7. Methodology- Variables IV- variations of odour (pleasant [cologne/geranium], unpleasant [body odour/rubber], or neutral [clean medical air])  IV- Attractiveness of the image (high or low) DV- rating of perceived attractiveness of male faces (1-9 scale with 1 lowest and 9 highest)

8. Methodology- Apparatuses 40 male faces chosen from work by Perrett (1998) http://www.perceptionlab.com/WEBPAGE/Research/Research.html http://www.perceptionlab.com/WEBPAGE/Research/Research.html  20 faces rated as “high” and 20 rated as “low” facial attractiveness 4 odours used in the study (from pilot research):  Pleasant odours: Gravity cologne & geranium  Unpleasant odours: rubber & synthetic body odour 2M3M  Neutral odour of ‘clean medical air’ also used to clear out the testing room Custom-built olfactometer to deliver the odourants  Flow was modulated through a regulator at adjusted concentrations to standardize procedure

9. Methodology- Design Lab study Repeated measures design with counterbalancing  The odours (including neutral) and the faces were presented multiple, specific times to eliminate demand characteristics Overall experimental session consisted of 3 blocks of 40 randomized trials (3 sets × 40 faces = 120 total) Each face was randomly presented 3 times during each experimental session (once with pleasant, once with unpleasant, & once with neutral)  Each time, the Ps rated the face

10. Methodology- Design To counterbalance the presentation of each face/odour combination, the 40 faces were divided into sub-groups of 10 each- 5 high and 5 low attractiveness per group  Resulted in 4 sets of pictures (40 total per set) that were seen with each face 3 times, resulting in 120 trials total from the combined 3 experimental sessions (each session also counterbalanced)  Each face was presented with one different pleasant odour, an unpleasant odour, and the clean medical air  The same odour was never presented on consecutive trials  A 5-minute break was given between each session Experiment lasted about 50 minutes total

11. Example block of trials breakdown Set 1Set 2Set 3Set 4 10 faces (5↑, 5↓) (each shown 3×) 10 faces (5↑, 5↓) (each shown 3×) 10 faces (5↑, 5↓) (each shown 3×) 10 faces (5↑, 5↓) (each shown 3×) Clean air Geranium Body odour Clean air Cologne Rubber Clean air Geranium Rubber Clean air Cologne Body odour

12. Methodology- Procedure 1. Participants sat 27 ½ inches from computer screen utilizing a chin rest to view the 5×7 image & look at the ‘X’ focal point  When they heard the ‘quiet tone,’ Ps start exhaling via nose and when they heard the ‘loud tone,’ Ps start inhaling via nose 2. The odour was delivered (P confirmed the scent by pushing a button on the keyboard) and the face appears for a ½ second 3. Screen goes black & clean air pumped in again 4. A 9-point scale was then presented on the screen for the Ps to rate the facial attractiveness of the pic  1 least attractive, 5 neutral, 9 most attractive 5. After rating selection, process repeated

13. Presentation of odour sequence

14. Methodology- Procedure Clean medical air was presented throughout the trials except when the odourant was delivered Ps given a 5 minute break after each trial to limit fatigue and/or olfactory adaptation At end of the experiment, Ps were asked to smell the odours individually and rate each on intensity, pleasantness, & familiarity from 0-100 on Labeled Magnitude Scale (LMS) Presentation of odours and scales were randomized among Ps

15. Labeled Magnitude Scale (LMS)

16. Results of the Study Highest mean facial attractiveness- male fragrance 5.73 Lowest mean facial attractiveness- body odor 3.64 Combined pleasant= 4.85, Combined unpleasant= 4.42, Neutral= 4.90

17. Results of the Study The rating of faces with odours revealed:  Results revealed a significant main effect of odour pleasantness on participants’ facial attractiveness rating Indicates that the odour (both pleasant an unpleasant) impacted the rating of the face by the Ps  Ps considered the faces as being significantly less attractive when presented with an unpleasant odour compared to a pleasant odour or clean air  However, there was no significant difference b/w pleasant versus neutral air ratings

18. Results of the Study The LMS data revealed:  Odour intensity scores revealed that the pleasant and unpleasant odours were perceived as more ‘intense’ than the clean air  Odour intensity scores revealed no significant difference b/w the intensity of the pleasant odour & the unpleasant odour  All three odour categories were judged to be equally familiar to the Ps

19. Conclusion Females are more likely to judge a male face as being :  (a) Slightly more attractive when presented with a pleasant odour or neutral odour  (b) Slightly less attractive when presented with an unpleasant odour There is no perceived difference in attractiveness between a face with a pleasant odour and a face with a neutral odour

20. Strengths and Weaknesses Strengths  ‘Standardized’ questioning to reduce variables of Ps  Controlled lab setting increases validity & is more replicable  Presentation of faces counterbalanced to control for ordering effects and demand characteristics  Faces used from the standardized database  Few (if any) ethical concerns Weaknesses  Demand characteristics possibilities  Low validity (ecological, construct)  Low generalization (pop/sample size)  Ethnocentric