Oxygenated-Blood Colour Change Thresholds for Perceived Facial Redness, Health, and Attractiveness

Abstract

Blood oxygenation level is associated with cardiovascular fitness, and raising oxygenated blood colouration in human faces increases perceived health. The current study used a two-alternative forced choice (2AFC) psychophysics design to quantify the oxygenated blood colour (redness) change threshold required to affect perception of facial colour, health and attractiveness. Detection thresholds for colour judgments were lower than those for health and attractiveness, which did not differ. The results suggest redness preferences do not reflect a sensory bias, rather preferences may be based on accurate indications of health status. Furthermore, results suggest perceived health and attractiveness may be perceptually equivalent when they are assessed based on facial redness. Appearance-based motivation for lifestyle change can be effective; thus future studies could assess the degree to which cardiovascular fitness increases face redness and could quantify changes in aerobic exercise needed to increase facial attractiveness.

Facial Redness Increases Men’s Perceived Healthiness and Attractiveness

“…Further, there is some empirical evidence that people associate increased facial redness with increased apparent health (Pazda, Thorstenson, Elliot, & Perrett, 2016;Re et al, 2011;Stephen, Law Smith, Stirrat, & Perrett, 2009;Stephen, Coetzee, Law Smith, & Perrett, 2009;. Therefore, in the current research we expected that facial redness would positively influence women's perceptions of men's healthiness.…”

“…CIELAB is considered to be a perceptually uniform color space, meaning that a change in one unit is equivalent in perceptual magnitude across the entire space. A change of a* = 5 reflects a suprathreshold color difference (the average Δa* threshold for facial redness discrimination is 0.67, SEM = 0.16, according to data from Re et al, 2011), meaning that participants should have been able to clearly perceive the color differences between the faces. Lightness, yellowness, hair, eyes, clothing, and background remained constant for each target.…”

“…Surprisingly, there is very little existing research examining the influence of men's facial redness on their perceived attractiveness when viewed by women. Recent studies revealed that both male and female facial color influenced their attractiveness (Re, Whitehead, Xiao, & Perrett, 2011;Carrito et al, 2016, Stephen et al, 2012, Said & Todorov, 2011, but the raters in these samples consisted of both men and women, and investigating the mechanisms behind such effects was not the central focus of this work.…”

Emotion-color associations in the context of the face.

“…Hagen, & Perrett, 2013;Re, Whitehead, Xiao, & Perrett, 2011;Tan & Stephen, 2013). This suggests that skin color plays an important role in social communication.…”

Discrimination of Attractiveness and Health in Men’s Faces: the Impact of Color Cues and Variation in Relation to Sex and Age of Rater

“…In studies in which participants manipulate color-calibrated facial images to optimize the appearance of health, raters appear to be sensitive to differences arising from variation in relative levels of oxygenated to deoxygenated blood color, suggesting this variation is important to perceptions of health in facial skin (Stephen et al 2009;Re et al 2011). Furthermore, changes in skin coloration also occur within as little as 1 h following experimental infection with a bacterial endotoxin, with changes varying in facial skin (becoming lighter and less red) compared to elsewhere on the body (Henderson et al 2017).…”