S. Craig Roberts

Affective Dimensions of Odor Perception: A Comparison Between Swiss, British, and Singaporean Populations

Do affective responses to odors vary as a function of culture? To address this question, we developed two self-report scales in the United Kingdom (Liverpool: LEOS) and in Singapore (city of Singapore: SEOS), following the same procedure as used in the past to develop the Geneva Emotion and Odor Scale (GEOS: Chrea, Grandjean, Delplanque et al., 2009). The final scales were obtained by a three-step reduction of an initial pool of 480 affective terms, retaining only the most relevant terms to describe odor-related subjective affective states and comprised of six (GEOS) or seven affective dimensions (LEOS and SEOS). These included dimensions that were common to the three cultures (Disgust, Happiness Well-being, Sensuality Desire, and Energy), common to the two European samples (Soothing Peacefulness), and dimensions that were culture specific (Sensory Pleasure in Geneva; Nostalgia and Hunger Thirst in Liverpool; Intellectual Stimulation, Spirituality, and Negative Feelings in Singapore). A comparative approach showed that the dimensional organization of odor-related affective terms in a given culture better explained data variability for that culture than data variability for the other cultures, thus highlighting the importance of culture-specific tools in the investigation of odor-related affect.

The perception of attractiveness and trustworthiness in male faces affects hypothetical voting decisions differently in wartime and peacetime scenarios

Facial appearance of candidates has been linked to real election outcomes. Here we extend these findings by examining the contributions of attractiveness and trustworthiness in male faces to perceived votability. We first use real faces to show that attractiveness and trustworthiness are positively and independently related to perceptions of good leadership (rating study). We then show that computer graphic manipulations of attractiveness and trustworthiness influence choice of leader (Experiments 1 and 2). Finally, we show that changing context from wartime to peacetime can affect which face receives the most votes. Attractive faces were relatively more valued for wartime and trustworthy faces relatively more valued for peacetime (Experiments 1 and 2). This pattern suggests that attractiveness, which may indicate health and fitness, is perceived to be a useful attribute in wartime leaders, whereas trustworthiness, which may indicate prosocial traits, is perceived to be more important during peacetime. Our studies highlight the possible role of facial appearance in voting behaviour and the role of attributions of attractiveness and trust. We also show that there may be no general characteristics of faces that make them perceived as the best choice of leader; leaders may be chosen because of characteristics that are perceived as the best for leaders to possess in particular situations.

Oral contraceptive use in women changes preferences for male facial masculinity and is associated with partner facial masculinity

Millions of women use hormonal contraception and it has been suggested that such use may alter mate preferences. To examine the impact of oral contraceptive (pill) use on preferences, we tested for within-subject changes in preferences for masculine faces in women initiating pill use. Between two sessions, initiation of pill use significantly decreased womens preferences for male facial masculinity but did not influence preferences for same-sex faces. To test whether altered preference during pill use influences actual partner choice, we examined facial characteristics in 170 age-matched male partners of women who reported having either been using or not using the pill when the partnership was formed. Both facial measurements and perceptual judgements demonstrated that partners of women who used the pill during mate choice have less masculine faces than partners of women who did not use hormonal contraception at this time. Our data (A) provide the first experimental evidence that initiation of pill use in women causes changes in facial preferences and (B) documents downstream effects of these changes on real-life partner selection. Given that hormonal contraceptive use is widespread, effects of pill use on the processes of partner formation have important implications for relationship stability and may have other biologically relevant consequences.

Hormonal contraceptive use and mate retention behavior in women and their male partners.

Female hormonal contraceptive use has been associated with a variety of physical and psychological side effects. Women who use hormonal contraceptives report more intense affective responses to partner infidelity and greater overall sexual jealousy than women not using hormonal contraceptives. Recently, researchers have found that using hormonal contraceptives with higher levels of synthetic estradiol, but not progestin, is associated with significantly higher levels of self-reported jealousy in women. Here, we extend these findings by examining the relationship between mate retention behavior in heterosexual women and their male partners and womens use of hormonal contraceptives. We find that women using hormonal contraceptives report more frequent use of mate retention tactics, specifically behaviors directed toward their partners (i.e., intersexual manipulations). Men partnered with women using hormonal contraceptives also report more frequent mate retention behavior, although this relationship may be confounded by relationship satisfaction. Additionally, among women using hormonal contraceptives, the dose of synthetic estradiol, but not of synthetic progesterone, positively predicts mate retention behavior frequency. These findings demonstrate how hormonal contraceptive use may influence behavior that directly affects the quality of romantic relationships as perceived by both female and male partners.

Perceived Aggressiveness Predicts Fighting Performance in Mixed-Martial-Arts Fighters

Accurate assessment of competitive ability is a critical component of contest behavior in animals, and it could be just as important in human competition, particularly in human ancestral populations. Here, we tested the role that facial perception plays in this assessment by investigating the association between both perceived aggressiveness and perceived fighting ability in fighters’ faces and their actual fighting success. Perceived aggressiveness was positively associated with the proportion of fights won, after we controlled for the effect of weight, which also independently predicted perceived aggression. In contrast, perception of fighting ability was confounded by weight, and an association between perceived fighting ability and actual fighting success was restricted to heavyweight fighters. Shape regressions revealed that aggressive-looking faces are generally wider and have a broader chin, more prominent eyebrows, and a larger nose than less aggressive-looking faces. Our results indicate that perception of aggressiveness and fighting ability might cue different aspects of success in male-male physical confrontation.

Revisiting the Red Effect on Attractiveness and Sexual Receptivity: No Effect of the Color Red on Human Mate Preferences

Color-in-context theory is the first theoretical framework for understanding color effects in human mate preferences, arguing that red clothing enhances attractiveness ratings. Here we present three empirical studies failing to support this prediction. We aimed to extend the current literature by differentiating color effects by temporal context (short-term vs. long-term mating). Experiment 1 involved Dutch participants rating a woman in red, white, and black on (sexual) attractiveness. Experiment 2 replicated the first experiment with an American sample. In the final experiment, we aimed to replicate a study that did find evidence of a red effect, using a substantially larger sample size. The results from each of the three studies (totaling N = 830 men) fail to support the red effect. We discuss the implications of our results and avenues for future research on red effects and attractiveness.

Evolution, appearance, and occupational success

Visual characteristics, including facial appearance, are thought to play an important role in a variety of judgments and decisions that have real occupational outcomes in many settings. Indeed, there is growing evidence suggesting that appearance influences hiring decisions and even election results. For example, attractive individuals are more likely to be hired, taller men earn more, and the facial appearance of candidates has been linked to real election outcomes. In this article, we review evidence linking physical appearance to occupational success and evaluate the hypothesis that appearance based biases are consistent with predictions based on evolutionary theories of coalition formation and leadership choice. We discuss why appearance based effects are so pervasive, addressing ideas about a “kernel of truth” in attributions and about coalitional psychology. We additionally highlight that appearance may be differently related to success at work according to the types of job or task involved. For example, leaders may be chosen because the characteristics they possess are seen as best suited to lead in particular situations. During a time of war, a dominant-appearing leader may inspire confidence and intimidate enemies while during peace-time, when negotiation and diplomacy are needed, interpersonal skills may outweigh the value of a dominant leader. In line with these ideas, masculine-faced leaders are favored in war-time scenarios while feminine-faced leaders are favored in peace-time scenarios. We suggest that such environment or task specific competencies may be prevalent during selection processes, whereby individuals whose appearance best matches perceived task competences are most likely selected, and propose the general term “task-congruent selection” to describe these effects. Overall, our review highlights how potentially adaptive biases could influence choices in the work place. With respect to certain biases, understanding their origin and current prevalence is important in order to potentially reduce discrimination in the work place.

Face, body and speech cues independently predict judgments of attractiveness

Abstract Research on human attraction frequently makes use of single-modality stimuli such as neutral-expression facial photographs as proxy indicators of an individuals attractiveness. However, we know little about how judgments of these single-modality stimuli correspond to judgments of stimuli that incorporate multi-modal cues of face, body and speech. In the present study, ratings of attractiveness judged from videos of participants introducing themselves were independently predicted by judgments of the participants facial attractiveness (a neutral-expression facial photograph masked to conceal the hairstyle), body attractiveness (a photograph of the upper body), and speech attractiveness (the soundtrack to the video). We also found that ratings of the face, body and speech were positively related to each other. Our results support the assumption that the single-modality stimuli used in much attractiveness research are valid proxy indicators of overall attractiveness in ecologically valid contexts, ...

Psychology of Fragrance Use: Perception of Individual Odor and Perfume Blends Reveals a Mechanism for Idiosyncratic Effects on Fragrance Choice

Cross-culturally, fragrances are used to modulate body odor, but the psychology of fragrance choice has been largely overlooked. The prevalent view is that fragrances mask an individuals body odor and improve its pleasantness. In two experiments, we found positive effects of perfume on body odor perception. Importantly, however, this was modulated by significant interactions with individual odor donors. Fragrances thus appear to interact with body odor, creating an individually-specific odor mixture. In a third experiment, the odor mixture of an individuals body odor and their preferred perfume was perceived as more pleasant than a blend of the same body odor with a randomly-allocated perfume, even when there was no difference in pleasantness between the perfumes. This indicates that fragrance use extends beyond simple masking effects and that people choose perfumes that interact well with their own odor. Our results provide an explanation for the highly individual nature of perfume choice.

Opposite-sex siblings decrease attraction, but not prosocial attributions, to self-resembling opposite-sex faces

Contextual cues of genetic relatedness to familiar individuals, such as cosocialization and maternal–perinatal association, modulate prosocial and inbreeding-avoidance behaviors toward specific potential siblings. These findings have been interpreted as evidence that contextual cues of kinship indirectly influence social behavior by affecting the perceived probability of genetic relatedness to familiar individuals. Here, we test a more general alternative model in which contextual cues of kinship can influence the kin-recognition system more directly, changing how the mechanisms that regulate social behavior respond to cues of kinship, even in unfamiliar individuals for whom contextual cues of kinship are absent. We show that having opposite-sex siblings influences inbreeding-relevant perceptions of facial resemblance but not prosocial perceptions. Women with brothers were less attracted to self-resembling, unfamiliar male faces than were women without brothers, and both groups found self-resemblance to be equally trustworthy for the same faces. Further analyses suggest that this effect is driven by younger, rather than older, brothers, consistent with the proposal that only younger siblings exhibit the strong kinship cue of maternal–perinatal association. Our findings provide evidence that experience with opposite-sex siblings can directly influence inbreeding-avoidance mechanisms and demonstrate a striking functional dissociation between the mechanisms that regulate inbreeding and the mechanisms that regulate prosocial behavior toward kin.