Is the perception of odour pleasantness shared across cultures and ecological conditions? Evidence from Amazonia, East Africa, New Guinea, Malaysia and Poland.

What makes an odour pleasant or unpleasant? The inherent properties of the constituent chemical compounds, or the nose of the beholder, driven by idiosyncratic differences and culture-specific learning? Here, 582 individuals, including Tanzanian Hadza hunter-gatherers, Amazonian Tsimane' horticulturalists, Yali from the Papuan highlands and two industrialized populations (Poles, Malaysians), rated the pleasantness of 15 odour samples. We find considerable similarities in odour assessments across cultures, but our data do not fully support a claim regarding the universality of smell preferences. Despite cross-cultural similarities in olfactory assessments, probably driven by odour properties, we suggest that odour availability in ecological and cultural niches bears an undeniable effect on human odour preferences.

Body odours as putative chemosignals in the father-child relationship: New insights on paternal olfactory kin recognition and preference from infancy to adolescence.

Children's body odours are effective chemical cues in the parent-child relationship. Mothers can recognize the odour of their child and prefer this odour over that of unfamiliar children. This effect is mediated by genetic similarity and developmental stage and is therefore suited to promote parental care at pre-pubertal stage, while facilitating incest avoidance at (post-)pubertal stage. The present study tested whether similar mechanisms apply to fathers. Therefore n = 56 fathers evaluated body odour samples of their own and of unfamiliar children in varying genetic and developmental stages. Genetic status was determined by human leucocyte antigen (HLA) profiling, developmental status by standardized assessment of pubertal status and steroid hormone concentration (estradiol, testosterone). Similar to mothers, fathers identified their own child's body odour above chance and preferred that odour. The paternal preference did not relate to HLA similarity but decreased with increasing age of the child. The decline was associated with higher pubertal stages in daughters only, which supports the hypothesis of odour-mediated incest prevention in opposite-sex parent-child dyads.

Gender differences in the relationship between neuroticism and odor memory.

Given the indications on the relationship between neuroticism and various olfactory functions as well as the emotionality of odor memory, it is surprising that no research so far has investigated whether neuroticism corresponds with odor memory performance. Thus, the purpose of our study was to address this question in the context of gender differences. Participants (73 men) completed the 60-items NEO Five Factor Inventory and participated in 32-items "Test for odor memory". In the separate analyses conducted for men and women, we demonstrated that women outperformed men regarding the number of correct odor recognitions in the odor memory test and had higher neuroticism level than men. Spearman correlation showed further that neuroticism was positively associated with D-prime (R = 0.3, p = .021) and the number of correct odor recognitions in women (R = 0.32, p = .014). This effect was, respectively, moderately (B10 = 5.2) and strongly confirmed using the Bayesian approach (B10 = 8). However, Bonferroni post-hoc correction for multiple comparisons further revealed that in case of neuroticism and the number of hits, as well as D-prime, alpha level was below significance, indicated by p = .006. The correlation between neuroticism level and odor memory performance was significantly higher in women compared to men (Z = 1.8, p = .038), while in case of neuroticism and D-prime, it was on a trend level (Z = 1.5, p = .074). Overall, the present results indicate that neuroticism might be linked to conscious odors' remembering for women, which can be explained by the warning role of odor memory and its connection to limbic structures, as well as by the higher level of neuroticism and odor memory performance in women compared to men.

Drinking alcohol appears to have no impact on self-perceptions of morality, aggressiveness, or intelligence.

People generally perceive themselves as moral but does this tendency change after alcohol consumption? In the current research, we tested whether alcoholic intoxication affects self-assessments of morality (i.e., the self-importance of moral identity and the moral self-concept), and we also tested self-assessment of aggressiveness and intelligence. We conducted a preregistered laboratory experiment with participants divided into three groups: alcohol intoxication (n = 106), placebo (n = 114), and control condition (n = 109). We did not detect statistically significant differences in self-assessments across conditions. These data are consistent with the conclusion that self-assessments of morality, aggressiveness, and intelligence may be too stable to be affected by the momentary changes in self-perception caused by alcoholic intoxication. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Comparing accuracy in voice-based assessments of biological speaker traits across speech types.

Nonverbal acoustic parameters of the human voice provide cues to a vocaliser's sex, age, and body size that are relevant in human social and sexual communication, and also increasingly so for computer-based voice recognition and synthesis technologies. While studies have shown some capacity in human listeners to gauge these biological traits from unseen speakers, it remains unknown whether speech complexity improves accuracy. Here, in over 200 vocalisers and 1500 listeners of both sexes, we test whether voice-based assessments of sex, age, height and weight vary from isolated vowels and words, to sequences of vowels and words, to full sentences or paragraphs. We show that while listeners judge sex and especially age more accurately as speech complexity increases, accuracy remains high across speech types, even for a single vowel sound. In contrast, the actual heights and weights of vocalisers explain comparatively less variance in listener's assessments of body size, which do not vary systematically by speech type. Our results thus show that while more complex speech can improve listeners' biological assessments, the gain is ecologically small, as listeners already show an impressive capacity to gauge speaker traits from extremely short bouts of standardised speech, likely owing to within-speaker stability in underlying nonverbal vocal parameters such as voice pitch. We discuss the methodological, technological, and social implications of these results.

Odor exposure and recall of a virtual reality crime scene: A preliminary study.

Environmental context reinstatement has a particular value for recall of information in forensic interviews. Since odors are valuable memory cues and can act as memory triggers, in our preliminary study we explored whether odor exposure can help people recall details of a crime scene. The study comprised 58 women and 15 men aged 22-35 who immersed in a carefully controlled environment closely resembling an actual crime setting, i.e., a virtual reality crime. Participants were exposed to an odor at encoding, recall, both or neither of these instances, yielding a total of 4 experimental groups that further completed a memory recall task. The crime scene content recall was tested in a free recall and a forced-response test immediately after seeing the crime scene and one month later. We found no significant effects of odor exposure on the free or the cued recall of the crime scene. The memory scores correlated neither with the self-assessed olfactory/visual sensitivity of the subjects, nor with the perceived odor pleasantness. These preliminary findings suggest that introduction of a vanilla odor while encoding and recalling a crime scene does not aid witness recall accuracy.

Love and affectionate touch toward romantic partners all over the world.

Touch is the primary way people communicate intimacy in romantic relationships, and affectionate touch behaviors such as stroking, hugging and kissing are universally observed in partnerships all over the world. Here, we explored the association of love and affectionate touch behaviors in romantic partnerships in two studies comprising 7880 participants. In the first study, we used a cross-cultural survey conducted in 37 countries to test whether love was universally associated with affectionate touch behaviors. In the second study, using a more fine-tuned touch behavior scale, we tested whether the frequency of affectionate touch behaviors was related to love in romantic partnerships. As hypothesized, love was significantly and positively associated with affectionate touch behaviors in both studies and this result was replicated regardless of the inclusion of potentially relevant factors as controls. Altogether, our data strongly suggest that affectionate touch is a relatively stable characteristic of human romantic relationships that is robustly and reliably related to the degree of reported love between partners.

Typical diet and type of economy do not predict food-sharing behaviors in three Tanzanian societies.

Food sharing behavior is a widely observed phenomenon, and it draws attention of scholars interested in finding both proximate and ultimate explanations of such practices. In the current study, we focused on possible socio-economic and environmental food-sharing predictors: type of economy (i.e., immediate-return vs. delayed-return) and typical diet composition (i.e., proportion of proteins and carbohydrates in typical daily caloric intake). We investigated whether members of three societies from Tanzania (N = 177), namely hunter-gatherers (Hadza), pastoralists (Datoga), and agriculturalists (Iraqw) differ with regard to food-sharing patterns in the Dictator Game and reactions to violations of the food-sharing norms in the Ultimatum Game. We found that neither the type of economy nor the typical diet influenced our outcomes. The results indicated, however, that food sharing behavior was positively predicted by certain individual-level characteristics: people of higher strength and lower body fat shared more food, and women were more willing to share food than men.

Odor-based context-dependent memory: influence of olfactory cues on declarative and nondeclarative memory indices.

Reinstating the olfactory learning context can increase access to memory information, but it is not fully clear which memory functions are subject to an enhancing odor context reinstatement effect. Here, we tested whether congruent odor context during encoding and recall positively affected declarative and nondeclarative memory scores using a novel method for manipulation of an odorous environment; namely, intranasal Nosa plugs. Recall of a text and a complex figure as well as performance in a priming task were assessed immediately and 1 wk after encoding. We found that congruent odor exposure at encoding and recall aided free retrieval of a story at delayed testing but had no significant effect on a complex figure recall or a word completion task. Differences between the assessed memory indices suggest that olfactory environmental cues may be primarily efficient in free verbal recall tasks.

Olfactory perception relates to food neophobia in adolescence.

OBJECTIVES: Food neophobia is a rejection or avoidance of novel food products. Despite the adaptive importance of this behavior, it exerts a negative influence on dietary habits and preferences. Sensory sensitivity relates to food neophobia and among specific sensory modalities, olfaction seems to be an obvious candidate for a correlate of this behavior as odor perception largely affects food intake and enjoyment. However, research on olfactory perception and food neophobia is scarce, and despite some promising results, the full picture of their association still awaits discovery. The aim of this study was to explore the relationship between food neophobia and olfaction in adolescents, a group that has not been included in the previous studies investigating this association. METHODS: We tested the olfactory perception-food neophobia relationship in 510 adolescents 15 to 17 y of age using a food neophobia questionnaire, a psychophysical odor identification test, a self-assessment of odor sensitivity, an odor significance questionnaire, and through odor pleasantness assessments. RESULTS: We observed significant correlations between food neophobia and all included measures of olfactory perception. CONCLUSION: The overall regression model suggested that self-assessed sensitivity and odor awareness were the most influential, olfaction-related predictors of food neophobia in adolescents.

"May I present you: my disgust!" - Declared disgust sensitivity in the presence of attractive models.

Disgust sensitivity differs among men and women, and this phenomenon has been observed across numerous cultures. It remains unknown why such sex differences occur, but one of the reasons may relate to differences in self-presentation. We tested that hypothesis in an experiment comprising 299 participants (49% women) randomly allocated into three groups. Each group completed the Three Domains Disgust Scale (TDDS) and rated how disgusting they found olfactory, visual, gustatory, and tactile disgust elicitors either when a male experimenter was present, a female experimenter was present, or no experimenter was present. We hypothesised that male participants in the female experimenter group would declare decreased levels of disgust sensitivity, and female participants in the male experimenter group would declare increased levels of disgust sensitivity. Results showed that despite sex differences in pathogen and sexual disgust, attractive experimenters did not evoke any differences in declared disgust across groups with one exception-both men and women self-presented as more sensitive to sexual disgust in the presence of the female experimenter. We discuss our findings in the light of evolutionary and social theories.

Emotional expression in human odour.

Recent work has demonstrated that human body odour alters with changing emotional state and that emotionally laden odours can affect the physiology and behaviour of people exposed to them. Here we review these discoveries, which we believe add to a growing recognition that the human sense of smell and its potential role in social interactions have been underappreciated. However, we also critically evaluate the current evidence, with a particular focus on methodology and the interpretation of emotional odour studies. We argue that while the evidence convincingly indicates that humans retain a capacity for olfactory communication of emotion, the extent to which this occurs in ordinary social interaction remains an open question. Future studies should place fewer restrictions on participant selection and lifestyle and adopt more realistic experimental designs. We also need to devote more consideration to underlying mechanisms and to recognise the constraints that these may place on effective communication. Finally, we outline some promising approaches to address these issues, and raise some broader theoretical questions that such approaches may help us to answer.

Blindness, But Not HMHA Anosmia, Predicts Loneliness: A Psychophysical Study.

Olfactory deficits can play a detrimental role in everyday social functioning. Perception of 3-hydroxy-3-methylhexanoic acid (HMHA)-a body odor component-could also be linked to this research area. However, no study so far has addressed the problem of HMHA perception in the context of the previously reported relationship between olfactory abilities and social difficulties. Here, we tested whether HMHA-specific anosmia predicted loneliness understood both as a cognitive evaluation of social participation and as one's social isolation, and we additionally analyzed the effects and correlates of HMHA perception in relation to sightedness. The study comprised 196 people, of whom 99 were blind. We found that subjects with blindness declared particularly high loneliness, but HMHA anosmia and the interaction of sightedness and HMHA anosmia predicted neither loneliness nor social withdrawal. In addition, HMHA pleasantness was positively associated with social withdrawal of the subjects with blindness and emotional loneliness correlated with HMHA familiarity regardless of sightedness.

Physical Spacing and Social Interaction Before the Global Pandemic.

Subsequent to the arrival of SARS-CoV-2 and emergence of COVID-19, policy to limit the further spread has focused on increasing distance between individuals when interacting, often termed social distancing although physical distancing is more accurate (Das Gupta and Wong in Canadian J Public Health 111:488-489, 2020; Gale in Is 'social distancing' the wrong term? Expert prefers 'physical distancing,' and the WHO agrees. The Washington Post, 2020; Sørensen et al. in Glob Health Promot, 28:5-14, 2021), and limiting the frequency of interaction by limiting/prohibiting non-essential and large-scale social gatherings. This research note focuses on social spacing, defined by distance and interaction, to offer a cross-cultural insight into social distancing and social interactions in the pre-pandemic period. Combining unique data on frequency of contact, religious service attendance and preferred interpersonal spacing in 20 countries, this research note considers variation in the extent to which physical distance was already practiced without official recommendations and underscores notable cross-cultural variation in the extent to which social interaction occurred. Results suggest that policy intervention should emphasize certain behavioral changes based on pre-existing context-specific patterns of interaction and interpersonal spacing rather than a one-size-fits-all approach. This research note is a descriptive first step that allows unique insight into social spacing and contact prior to the spread of SARS-CoV-2. It provides a baseline typology and a reference for future work on the cross-cultural implications of COVID-19 for pre-pandemic socio-cultural practice and vice versa.

Interpersonal distancing preferences, touch behaviors to strangers, and country-level early dynamics of SARS-CoV-2 spread.

The recent Coronavirus Disease 2019 (COVID-19) pandemic has led to "social distancing" recommendations from public health organizations, as physical closeness bears the risk of person-to-person Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) transmission. Here, it was explored if interpersonal distance preferences and touch behaviors in 41 countries were valid measures of physical distancing in contacts between strangers and whether they related to country-level variation in early dynamics of SARS-CoV-2 spread. The analysis, based on aggregated data from more than 9,000 participants, showed that variation in early dynamics of SARS-CoV-2 spread (i.e., total number of SARS-CoV-2 cases 20 days after the 100th case) was significantly and positively related to nonaffective touch behaviors between strangers, and significantly and negatively related to the preferred interpersonal distance between strangers. These findings suggest that the two measures are suitable for monitoring the extent to which recommendations on physical distance are implemented at the country-level in the context of COVID 19 outbreak. Further, they confirm that "physical distancing" is related to the dynamics of the COVID-19 pandemic. It seems that an adaptation of social behaviors-that is, strict physical distancing from strangers-may result in a lower SARS-CoV-2 transmission rate. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

No evidence for association between human body odor quality and immune system functioning.

Previous studies have shown that women perceive male faces with a more reactive immune system as more attractive, but whether body odor might likewise provide cues to immune function has not been investigated yet. These two studies tested a possible relationship between body odor quality and immunoreactivity (Study 1) and immune system function (Study 2). In Study 1, we collected body odor samples from 21 men just before and two weeks after vaccination against hepatitis A/B and meningococcus. We determined the levels of specific antibodies (selected as markers of immune system's reactivity), testosterone, and cortisol. Subsequently, 88 female raters assessed the odor samples for their attractiveness, intensity, and healthiness. In Study 2, we collected body odor and blood samples from 35 men and women. We assessed key parameters of their innate and adaptive immunity, such as complement activity or total lymphocyte T and B counts and asked 95 raters to assess the odor samples for their attractiveness, intensity, and healthiness. In Study 1, we found no significant association between antibody levels induced by vaccination and perceived body odor attractiveness, intensity, and healthiness. We also found no significant relationship between antibody levels and steroid hormones (testosterone and cortisol). In Study 2, we likewise found no association between basal key parameters (innate and adaptive) of the immune system and body odor quality. Our results indicate that body odor may not serve as a cue to the reactivity of the immune system.

Sex differences in human mate preferences vary across sex ratios.

A wide range of literature connects sex ratio and mating behaviours in non-human animals. However, research examining sex ratio and human mating is limited in scope. Prior work has examined the relationship between sex ratio and desire for short-term, uncommitted mating as well as outcomes such as marriage and divorce rates. Less empirical attention has been directed towards the relationship between sex ratio and mate preferences, despite the importance of mate preferences in the human mating literature. To address this gap, we examined sex ratio's relationship to the variation in preferences for attractiveness, resources, kindness, intelligence and health in a long-term mate across 45 countries (n = 14 487). We predicted that mate preferences would vary according to relative power of choice on the mating market, with increased power derived from having relatively few competitors and numerous potential mates. We found that each sex tended to report more demanding preferences for attractiveness and resources where the opposite sex was abundant, compared to where the opposite sex was scarce. This pattern dovetails with those found for mating strategies in humans and mate preferences across species, highlighting the importance of sex ratio for understanding variation in human mate preferences.

Affective Interpersonal Touch in Close Relationships: A Cross-Cultural Perspective.

Interpersonal touch behavior differs across cultures, yet no study to date has systematically tested for cultural variation in affective touch, nor examined the factors that might account for this variability. Here, over 14,000 individuals from 45 countries were asked whether they embraced, stroked, kissed, or hugged their partner, friends, and youngest child during the week preceding the study. We then examined a range of hypothesized individual-level factors (sex, age, parasitic history, conservatism, religiosity, and preferred interpersonal distance) and cultural-level factors (regional temperature, parasite stress, regional conservatism, collectivism, and religiosity) in predicting these affective-touching behaviors. Our results indicate that affective touch was most prevalent in relationships with partners and children, and its diversity was relatively higher in warmer, less conservative, and religious countries, and among younger, female, and liberal people. This research allows for a broad and integrated view of the bases of cross-cultural variability in affective touch.

Universality of the Triangular Theory of Love: Adaptation and Psychometric Properties of the Triangular Love Scale in 25 Countries.

The Triangular Theory of Love (measured with Sternberg's Triangular Love Scale - STLS) is a prominent theoretical concept in empirical research on love. To expand the culturally homogeneous body of previous psychometric research regarding the STLS, we conducted a large-scale cross-cultural study with the use of this scale. In total, we examined more than 11,000 respondents, but as a result of applied exclusion criteria, the final analyses were based on a sample of 7332 participants from 25 countries (from all inhabited continents). We tested configural invariance, metric invariance, and scalar invariance, all of which confirmed the cultural universality of the theoretical construct of love analyzed in our study. We also observed that levels of love components differ depending on relationship duration, following the dynamics suggested in the Triangular Theory of Love. Supplementary files with all our data, including results on love intensity across different countries along with STLS versions adapted in a few dozen languages, will further enable more extensive research on the Triangular Theory of Love.