Claire A. Conway

Raised salivary testosterone in women is associated with increased attraction to masculine faces.

Womens preferences for masculinity in mens faces, voices and behavioral displays change during the menstrual cycle and are strongest around ovulation. While previous findings suggest that change in progesterone level is an important hormonal mechanism for such variation, it is likely that changes in the levels of other hormones will also contribute to cyclic variation in masculinity preferences. Here we compared womens preferences for masculine faces at two points in the menstrual cycle where women differed in salivary testosterone, but not in salivary progesterone or estrogen. Preferences for masculinity were strongest when womens testosterone levels were relatively high. Our findings complement those from previous studies that show systematic variation in masculinity preferences during the menstrual cycle and suggest that change in testosterone level may play an important role in cyclic shifts in womens preferences for masculine traits.

Integrating Gaze Direction and Expression in Preferences for Attractive Faces

Few studies have investigated how physical and social facial cues are integrated in the formation of face preferences. Here we show that expression differentially qualifies the strength of attractiveness preferences for faces with direct and averted gaze. For judgments of faces with direct gaze, attractiveness preferences were stronger for smiling faces than for faces with neutral expressions. By contrast, for judgments of faces with averted gaze, attractiveness preferences were stronger for faces with neutral expressions than for smiling faces. Because expressions can differ in meaning depending on whether they are directed toward or away from oneself, it is only by integrating gaze direction, facial expression, and physical attractiveness that one can unambiguously identify the most attractive individuals who are likely to reciprocate ones own social interest.

Salience of emotional displays of danger and contagion in faces is enhanced when progesterone levels are raised.

Findings from previous studies of hormone-mediated behavior in women suggest that raised progesterone level increases the probability of behaviors that will reduce the likelihood of disruption to fetal development during pregnancy (e.g. increased avoidance of sources of contagion). Here, we tested womens (N=52) sensitivity to potential cues to nearby sources of contagion (disgusted facial expressions with averted gaze) and nearby physical threat (fearful facial expressions with averted gaze) at two points in the menstrual cycle differing in progesterone level. Women demonstrated a greater tendency to perceive fearful and disgusted expressions with averted gaze as more intense than those with direct gaze when their progesterone level was relatively high. By contrast, change in progesterone level was not associated with any change in perceptions of happy expressions with direct and averted gaze, indicating that our findings for disgusted and fearful expressions were not due to a general response bias. Collectively, our findings suggest women are more sensitive to facial cues signalling nearby contagion and physical threat when raised progesterone level prepares the body for pregnancy.

Perceived vulnerability to disease is positively related to the strength of preferences for apparent health in faces

People who are particularly vulnerable to disease may reduce their likelihood of contracting illnesses during social interactions by having particularly strong aversions to individuals who appear ill. Consistent with this proposal, here we show that men and women who perceive themselves to be particularly vulnerable to disease have stronger preferences for apparent health in dynamic faces than individuals who perceive themselves to be relatively less vulnerable to disease. This relationship was independent of possible effects of general disgust sensitivity. Furthermore, perceived vulnerability to disease was not related to preferences for other facial cues that are attractive but do not necessarily signal an individuals current health (i.e. perceiver-directed smiles). Our findings complement previous studies implicating perceived vulnerability to disease in attitudes to out-group individuals and those with physical abnormalities by implicating perceived vulnerability to disease as a factor in face preferences. Collectively, our findings reveal a relatively domain-specific association between perceived vulnerability to disease and the strength of aversions to facial cues associated with illness. Additionally, they are further evidence that variation in attractiveness judgments is not arbitrary, but rather reflects potentially adaptive individual differences in face preferences.

HORMONAL CONTRACEPTIVE USE AND PERCEPTIONS OF TRUST MODULATE THE EFFECT OF RELATIONSHIP CONTEXT ON WOMEN'S PREFERENCES FOR SEXUAL DIMORPHISM IN MALE FACE SHAPE

Women demonstrate stronger preferences for femininity when assessing mens attrac- tiveness for long-term rather than short-term relationships. One explanation of this effect is that the pro-social traits associated with femininity are particularly important for long-term relation- ships. This explanation has recently been challenged, however, following null findings for effects of pro-social attributions on womens preferences for feminine long-term partners. A limitation of these latter analyses is that they did not consider hormonal contraceptive use, which is a factor that previous studies suggest affects mate preferences. In our study, we found that women not using hormonal contraceptives demonstrated stronger preferences for femininity in mens faces when assessing men as long-term partners than when assessing men as short-term partners. More- over, this effect was most pronounced among women who perceived feminine men as particularly trustworthy. No equivalent effects were observed among women using hormonal contraceptives. These findings support the proposal that the effect of relationship context on womens face pref- erences occurs, at least in part, because women value pro-social traits more in long-term than short-term partners. Additionally, our findings suggest that both hormonal contraceptive use and individual differences in perceptions of pro-social traits modulate the effect of relationship con- text on womens face preferences.

Transient pupil constrictions to faces are sensitive to orientation and species

Previous studies have reported transient pupil constrictions to basic visual attributes (e.g., color and movement) that are processed along the ventral and the dorsal pathways. Specific cortical areas are activated more for faces than most other types of stimuli, raising the possibility that stimulus-specific transient pupil constrictions might also occur for faces. Such pupil responses may be sensitive to stimulus orientation and species since these parameters have been found to affect electrophysiological and behavioral responses to faces. Here we show transient pupil constrictions to upright human faces that are greater than those to scrambled versions, inverted versions, or macaque monkey faces. Similar to findings from electrophysiological studies, the inversion effect occurred for human faces but not macaque faces. Collectively, our findings show that transient pupil constrictions to faces are sensitive to the same parameters that have been found to influence electrophysiological and behavioral measures of face processing (i.e., orientation and species) and thus reveal a novel, objective, and non-invasive method for studying face perception.

Integrating physical and social cues when forming face preferences: Differences among low and high-anxiety individuals

Abstract This study investigated individual differences in the integration of social (i.e., direction of social interest) and physical (i.e., apparent health) cues in a face preference test. While low-anxiety individuals demonstrated preferences for social engagement from healthy-looking faces, but not from unhealthy-looking faces, high-anxiety individuals preferred social engagement from both healthy and unhealthy individuals. Importantly, anxious individuals were not simply less discriminating in their face preferences generally: anxiety levels were positively related to the strength of overall preferences for positive social interest. Collectively, our findings show that perceptions of gaze and expression can be modulated by aspects of facial appearance and that systematic variation among individuals exists in the extent to which this modulation occurs. Furthermore, since previous studies have demonstrated hypersensitive amygdala responses among anxious individuals when viewing faces, our findings suggest that the amygdala may play an important role in determining how different facial cues are integrated in person perception.

View-contingent aftereffects suggest joint coding of face shape and view.

While it is well established that different neural populations code different face views, behavioural evidence that these neurons also code other aspects of face shape is equivocal. For example, previous studies have interpreted the partial transfer of face aftereffects across different viewpoints as evidence for either view-specific coding of face shape or that the locus of adaptation is in face-coding mechanisms that are relatively robust to changes in face view. Here we show that it is possible to simultaneously induce aftereffects in opposite directions for 3/4 and front views of upright faces with manipulated mouth position (experiment 1). For example, simultaneous adaptation to 3/4 views with raised mouth position and front views with lowered mouth position caused raised mouth position to appear more normal for 3/4 views of novel faces, but less normal for front views. View-contingent adaptation did not occur for inverted faces, however (experiment 2). Dissociable aftereffects for different views of upright faces, but not for different views of inverted faces, suggest that neurons that code face view can also code other aspects of face shape.