The role of body odors and olfactory ability in the initiation, maintenance and breakdown of romantic relationships - A review

[What is happiness? And what does ENT medicine have to do with it?]

Happiness is important to most people in our society, although it is given little importance in political and social objectives. However, happiness is an important topic in various philosophical schools and in Western philosophy, happiness goes back to Aristotelianism and Stoic philosophy. Recent longitudinal studies clearly suggest that happiness depends on interpersonal relationships. So what does otorhinolaryngology have to do with this? In our view, various basic skills that enable people to achieve social fitness, i.e., to establish short- and long-term relationships, are at the center of ENT medicine. Examples of this are hearing, olfaction, the voice, but also facial movements. The multisensory processing of various perception and expression channels creates a "social brain network" as a neuronal correlate of social skills and fitness. Consequently, otorhinolaryngology should play a central role in understanding these abilities in the context of happiness.

The Scent of Intimacy: Exploring the Associations Between Intimacy, Disgust, and Olfactory Ability

Intimacy is a fundamental aspect of romantic relationships, yet its underlying sensory mechanisms remain understudied. Research has suggested that experiences of intimacy are related to both olfaction and disgust. For example, studies indicate greater olfactory ability is associated with fulfilling relationships, while heightened disgust sensitivity can hinder sexual arousal and interpersonal affiliation. However, no study has investigated intimacy, olfaction, and disgust together. To investigate this, 74 participants aged 17-56 years (M = 22.6, SD = 7.1), completed self-report surveys assessing relationship intimacy and sensitivity to pathogen, moral, and sexual disgust. Participants also completed a short form of the Sniffin' Sticks identification test. Results revealed emotional and intellectual intimacy shared a significant weak positive association with olfactory ability, and no significant relationship with any form of disgust. Physical intimacy had a significant weak positive relationship with pathogen and sexual disgust, but not olfactory ability or moral disgust. Social intimacy had a significant positive moderate relationship with only pathogen disgust. Findings highlight the multifactorial nature of relationships and the importance of exploring different factors that may relate to intimacy.

The impact of COVID-19-related smell dysfunction on sexual and mental wellbeing: Data from a longitudinal sample

OBJECTIVE

Olfactory disorders are associated with poor sexual and mental wellbeing, but prior work mainly consists of retrospective and cross-sectional reports. The current study assessed their prospective associations.

METHODS

73 patients with COVID-19-associated olfactory dysfunction were recruited between 2021 and 2023 at a Smell Clinic in Dresden, Germany. Patients were assessed twice, about 6 months apart. On each occasion, patients' olfactory functioning (i.e., psychophysical tests and self-rated function) and sexual and mental wellbeing were measured (i.e., sexual frequency, sexual desire, wellbeing, anxiety symptoms, and depressive symptoms).

RESULTS

Within-person improvements in psychophysical olfactory functioning were associated with increased sexual frequency. In a subset of 51 people in stable romantic partnerships, improved psychophysical olfactory functioning predicted increased sexual frequency and increased sexual desire. No evidence emerged supporting an association between improvements in olfactory functioning and mental health or wellbeing outcomes CONCLUSIONS: A decline in sexual function may be an early reaction to olfactory dysfunction. Individuals with recent onset of olfactory disorders may benefit from sexual health support.

Why dogs prefer zoomies to zoom and what it tells us about the importance of in-person meetings for learning and memory

As people commonly observe dog behaviors like the sudden bursts of physical movement colloquially known as "zoomies," and the canine penchant for sticking their nose out of car windows and for sniffing intently in dog parks, it is not surprising that people generally believe dogs learn and communicate by smell. While people generally discount their own olfactory sensitivity and the importance of smell overall, humans also learn and communicate by smell, in some cases even better than dogs. In this article, we discuss why this information exchange matters for learning and memory and why virtual meetings don't pass the sniff test.

Past, Present, and Future of Human Chemical Communication Research

Although chemical signaling is an essential mode of communication in most vertebrates, it has long been viewed as having negligible effects in humans. However, a growing body of evidence shows that the sense of smell affects human behavior in social contexts ranging from affiliation and parenting to disease avoidance and social threat. This article aims to (a) introduce research on human chemical communication in the historical context of the behavioral sciences; (b) provide a balanced overview of recent advances that describe individual differences in the emission of semiochemicals and the neural mechanisms underpinning their perception, that together demonstrate communicative function; and (c) propose directions for future research toward unraveling the molecular principles involved and understanding the variability in the generation, transmission, and reception of chemical signals in increasingly ecologically valid conditions. Achieving these goals will enable us to address some important societal challenges but are within reach only with the aid of genuinely interdisciplinary approaches.

The association between interoception and olfactory affective responses

Odors are known to affect an individual's emotions and physiological states. Recent research has revealed that olfaction is linked to the mental representation of internal sensations, known as interoception. However, little research has examined how interoception relates to emotional responses to odors. This research aimed to fill this gap in the literature. We conducted two studies with a total of 548 Japanese women (n = 500 and n = 48 in Studies 1 and 2, respectively). Study 1 used an online survey to assess the relationship between self-reported interoceptive traits and the intensity of positive emotions in response to daily odors. Study 2 examined how self-reported interoceptive traits modulated the arousal ratings of odors presented in the laboratory and the concordance between these perceived arousal ratings and odor-evoked physiological responses. Study 1 confirmed that self-reported interoceptive traits were significant predictors of positive emotional intensity of odors. In Study 2, individuals with high interoceptive measure scores showed concordance between their perceived emotional arousal and the physiological responses associated with that emotion, whereas individuals with low scores did not. These findings suggest that how people perceive their internal sensations contributes to shaping their olfactory affective experiences, thereby broadening the scope of interoception research and aromachology. The practical implications of these findings for the development of commercial fragrances are discussed.

Current opportunities and challenges of immersive virtual reality for psychological research and application

Immersive virtual reality (iVR), that is, digital stereoscopic 360° scenarios usually presented in head-mounted displays, has gained much popularity in medical, educational, and consumer contexts in the last years. Recently, psychological research started to utilize the theoretical and methodological advantages of iVR. Furthermore, understanding cognitive, emotional, and behavioral processes in iVR similar to real-life is a genuinely psychological, currently understudied topic. This article briefly reviews the current application of iVR in psychological research and related disciplines. The review presents empirical evidence for opportunities and strengths (e.g., realism, experimental control, effectiveness of therapeutic and educational interventions) as well as challenges and weaknesses (e.g., differences in experiencing presence, interacting with VR content including avatars, i.e., graphical representation of a person). The main part discusses areas requiring additional basic research, such as cognitive processes, socio-emotional processes during social interactions in iVR, and possible societal implications (e.g., fraud, VR-addiction). For both research and application, iVR offers a contemporary extension of the psychological toolkit, offering new avenues to investigate and enhance core phenomena of psychology such as cognition, affect, motivation, and behavior. Still, it is crucial to exercise caution in its application as excessive and careless use of iVR can pose risks to individuals' mental and physical well-being.

The Context Matters: Women's Experiences of Their Partner's Odor in Intimate and Sexual Encounters

Research shows that male body odor plays an important role in women's mate choice and that olfactory abilities are associated with women's sexual functioning. What remains unclear is what types of partner's odor actually shape women's experience during intimate activities. This study therefore explored women's experience associated with the partner's various odors and investigated how they affect women's intimate and sexual encounters. We performed semi-structured individual interviews with 20 single women and 20 women in a long-term relationship. Thematic analysis revealed four key natural odor types of the partner: body odor, sweat, genital odor, and semen odor. Further, we have identified three main types of fragrance odor (cologne, shower gel, and laundry agents) and investigated their perception in both intimate (hugging, kissing, cuddling, lying side by side) and sexual (intercourse, oral sex, ejaculation) contexts. Both partner's natural odor and fragrance affected women's emotional state (ranging from pleasant to unpleasant) and behavioral response (ranging from approach to avoidance of partner). Women's odor perception was frequently context-dependent, so that even mostly negatively perceived odors (e.g., semen, genital odor) were often accepted as part of sexual encounter. Finally, women's perception was negatively modified by partner's specific sweat (after workday, workout, or when the partner is ill) during intimate encounters. Our results highlight the complexity and interindividual variability of partner's odor perception.

Male Body Odor Affects Emotional State, LH, and Cortisol Secretion in Women of Different Age Groups

Hormone changes across women's menstrual cycles may lead to changes in their perceptions of chemical signals and their hormonal responses to these cues. The aim of the present study was to determine the role of menstrual cycle phase in the response to extracts of male axillary secretions (EMAS) in women. We tested healthy reproductive age and premenopausal women (n = 29). An EMAS/control solution was applied once every two hours during either the follicular or luteal phase, at which point saliva samples for luteinizing hormone (LH) and cortisol monitoring were collected. LH and cortisol concentrations were analyzed using the enzyme immunoassay (EIA) technique. Positive and Negative Affect Schedule (PANAS) and Visual Analogue Scales (VAS) scores were used to assess the participants' moods. For the first time, we showed that EMAS may produce opposite effects on LH secretion depending on the menstrual cycle phase of the recipient. We observed a significant increase in the number of LH peaks (p = 0.0447) and their amplitudes (p = 0.0469) when EMAS was applied during the follicular phase, while the same application in the luteal phase lowered the amplitudes of LH peaks (p = 0.0382). For the first time, we showed that EMAS application increased salivary cortisol levels in reproductive age women relative to premenopausal women (p = 0.0032). PANAS scores revealed changes in positive and negative affect after EMAS application. Our data indicate the significance of the menstrual cycle phase for EMAS' effects on LH secretion and mood, but not on cortisol secretion in women.

The olfactory diary: Tracking awareness and consciousness of the sense of smell throughout the day

Objectives

The aim of the present study was to follow the daily course of patients with olfactory dysfunction and healthy controls and to assess (i) how many times a day, (ii) at which time, and (iii) in which aspect of daily life participants are conscious about their sense of smell.

Methods

In this longitudinal study, 49 patients with smell loss and 30 healthy participants were enrolled. Olfactory function was assessed using the Sniffin' Sticks. All participants received paper diaries designed for a 14-day period, featuring 12 rows representing 12 daily hours and six columns for various daily life aspects. They were instructed to mark their awareness of smell by indicating the relevant row and column in the diary. Following the return of the diaries, a second olfactory test was conducted within the patient group.

Results

On average, patients were consciously aware of their sense of smell around 8 times daily, while healthy participants noted it about 6.5 times a day. Both groups primarily focused on their sense of smell during activities related to "eating," followed by considerations in "social life" and "personal hygiene." Interestingly, distinct patterns emerged: patients peaked in awareness at 8 a.m. and 7 p.m., whereas healthy individuals showed peaks at 6 a.m., 12 p.m., and 7 p.m. Despite regular diary use, we observed no improvement in patients' olfactory function or related quality of life.

Conclusion

The olfactory diary is a valuable tool unveiling individual smell awareness patterns in patients with smell loss, aiding in counseling and patient management.

Level of Evidence

4.

Identification of the needs of individuals affected by COVID-19

BACKGROUND

The optimal management of COVID-19 symptoms and their sequelae remains an important area of clinical research. Policy makers have little scientific data regarding the effects on the daily life of affected individuals and the identification of their needs. Such data are needed to inform effective care policy.

METHODS

We studied 639 people with COVID-19 resident in France via an online questionnaire. They reported their symptoms, effects on daily life, and resulting needs, with particular focus on olfaction.

RESULTS

The results indicate that a majority of participants viewed their symptoms as disabling, with symptoms affecting their physical and mental health, social and professional lives. 60% of the individuals reported having unmet medical, psychological and socio-professional support needs. Finally, affected individuals were concerned about the risk and invasiveness of possible treatments as shown by a preference for non-invasive intervention over surgery to cure anosmia.

CONCLUSIONS

It is important that policy makers take these needs into consideration in order to assist affected individuals to regain a normal quality of life.

"Death and Love Amid the COVID-19 Pandemic": Effects of Pathogen Threats on Online Dating and Social Distancing From Life-History Strategy Perspectives

Drawing from the terror management theory (TMT) and evolutionary perspectives of Life-History Strategy, a between-subject online experiment examined the interaction effects of pre-existing death anxiety, fear-inducing media content (coronavirus threat vs. gun violence threat vs. low threat mental disorder), and intrasexual competition for mates on online dating intentions and social distancing intentions during the COVID-19 pandemic. Results indicate the interaction effects of participants' pre-experimental death anxiety and different types of fear-inducing media content on perceived fear and intention to use online dating websites/apps as well as the interaction effects of pre-experimental intrasexual competitiveness and fear-inducing media content on social distancing intention in the context of online dating. Theoretical contributions to the terror management literature and practical implications for the online dating industry are discussed.

Consistent social odor representation across 7 languages: the Social Odor Scale translation and validation

The Social Odor Scale (SOS) is a 12-item questionnaire initially developed and validated in Italian and German to investigate self-reported awareness of social odors, which are odors emanating from the human body that convey diverse information and evoke various emotional responses. The scale includes a total score and 3 subscales representing social odors in the respective categories: romantic partner, familiar, and strangers. Here, we aimed to (i) replicate the validation of the Italian and German versions of the SOS, (ii) translate and validate the SOS into multiple additional languages (French, English, Dutch, Swedish, Chinese), and (iii) explore whether the factor structure of each translated version aligns with the original versions. Confirmatory Factor Analysis (CFA) supported the scale's structure, yielding a good fit across all languages. Notable differences in SOS mean scores were observed among the different languages: Swedish participants exhibited lower social odor awareness compared to the other groups, whereas Chinese participants reported higher social odor awareness compared to Dutch and Swedish participants. Furthermore, SOS scores correlated with respondents' geographical location, with higher (i.e. northern) latitudes linked to lower social odor awareness. These results corroborate the SOS as a valid and reliable instrument, especially for the SOS total score and the Familiar and Partner factors, emphasizing the influence of individual and geographic factors on social odor awareness.

Intrinsic and extrinsic factors affecting axillary odor variation. A comprehensive review

Humans produce odorous secretions from multiple body sites according to the microbiomic profile of each area and the types of secretory glands present. Because the axilla is an active, odor-producing region that mediates social communication via the sense of smell, this article focuses on the biological mechanisms underlying the creation of axillary odor, as well as the intrinsic and extrinsic factors likely to impact the odor and determine individual differences. The list of intrinsic factors discussed includes sex, age, ethnicity, emotions, and personality, and extrinsic factors include dietary choices, diseases, climate, and hygienic habits. In addition, we also draw attention to gaps in our understanding of each factor, including, for example, topical areas such as the effect of climate on body odor variation. Fundamental challenges and emerging research opportunities are further outlined in the discussion. Finally, we suggest guidelines and best practices based on the factors reviewed herein for preparatory protocols of sweat collection, data analysis, and interpretation.

Smells as Communication Pathways - why Emotions Pass through the Nose

For many species, the sense of smell is the most important sensory system for interacting with the environment and conspecifics. In contrast, the role of perception and communication of chemosensory information in humans has long been underestimated. The human sense of smell was considered less reliable, so that it was given less importance compared to visual and auditory sensory impressions. For some time now, a growing branch of research has been dealing with the role of the sense of sell in emotion and social communication, which is often only perceived subconsciously. This connection will be examine in more detail in this article. First, he basics regarding the structure and function of our olfactory system will be described for better understanding and classification. Then, with this background knowledge, the significance of olfaction for interpersonal communication and emotions will be discussed. Finally, we conclude that people suffering from olfactory disorders have specific impairments in their quality of life.

Sniffing of Body Odors and Individual Significance of Olfaction Are Associated with Sexual Desire: A Cross-Cultural Study in China, India, and the USA

Olfactory sensations contribute to sexual desire and sexual behavior. However, the degree to which individual importance of olfactory function and body odors relate to sexual desire is not known. This study was conducted to preliminarily examine these relationships among Chinese college students (N = 1903) via the Importance of Olfaction Questionnaire, the Body Odor Sniffing Questionnaire, and the Sexual Desire Inventory, which were used to measure subjective significance of olfaction, frequency of sniffing self or others, and sexual desire, respectively. Individuals who assigned higher importance to olfaction or engaged more in body odor sniffing showed stronger sexual desire. We further explored these associations in different cultures to determine whether cultural consistency existed. We conducted a second study to make cross-cultural comparisons between Indian (N = 313) and US (N = 249) populations. For both countries, a higher importance placed on olfaction and a higher prevalence of body odor sniffing were consistently associated with stronger sexual desire. In conclusion, our study confirmed that people who placed more value on olfactory function or engaged more in body odor sniffing showed stronger sexual desire. These correlations were consistent for both sexes and across different cultures, further indicating the importance of olfaction in sexuality.

Olfactory training - Thirteen years of research reviewed

The sense of smell is interrelated with psychosocial functioning. Olfactory disorders often decrease quality of life but treatment options for people with olfactory loss are limited. Additionally, olfactory loss accompanies and precedes psychiatric and neurodegenerative diseases. Regular, systematic exposure to a set of odors, i.e., olfactory training (OT) has been offered for rehabilitation of the sense of smell in clinical practice. As signals from the olfactory bulb are directly projected to the limbic system it has been also debated whether OT might benefit psychological functioning, i.e., mitigate cognitive deterioration or improve emotional processing. In this review we synthesize key findings on OT utility in the clinical practice and highlight the molecular, cellular, and neuroanatomical changes accompanying olfactory recovery in people with smell loss as well as in experimental animal models. We discuss how OT and its modifications have been used in interventions aiming to support cognitive functions and improve well-being. We delineate main methodological challenges in research on OT and suggest areas requiring further scientific attention.

The Scent of Monogamy: Self-Reported Olfactory Function Predicts Sexual Well-Being and Infidelity in an Italian Population

Previous studies have shown that olfactory function plays an essential role in the bonding of a romantic relationship. Body odors, in particular, seem involved in both mate choices and other intimate behaviors. Our sense of smell is also crucial to detect possible pathogen threats, by activating a suitable disgust reaction. Previous studies have shown that disgust sensitivity is negatively related to sociosexuality, and disgust generally inhibits our sexual drive. In the present study, we explored the possible relation between olfactory function, pathogen disgust sensitivity, sociosexuality, sexual well-being, and infidelity through a web survey. Our exploratory analyses found that, in a large Italian sample (N = 1107), among those in a stable relationship, self-reported olfactory function predicted sexual well-being (p < .05) and negatively predicted infidelity (p < .05) when controlling for other relevant sociodemographics variables. Moreover, the relation between self-reported olfactory function and sexual well-being was mediated by pathogen disgust sensitivity. Although significant, these results must be interpreted with caution, because the effect sizes were small.

Do you often sniff yourself or others? Development of the Body Odor Sniffing Questionnaire and a cross-cultural survey in China and the USA

OBJECTIVES

Body odor can convey much information about an individual and thus we frequently engage in sniffing one's own and other people's body odor. However, there is scarce evidence on the within- and cross-cultural variation in body odor sniffing behaviors and no psychometric scale for specifically measuring such behaviors. Hence, our study aimed to develop the Body Odor Sniffing Questionnaire (BOSQ) and used it to make a cross-cultural comparison.

METHODS

In Study 1, 2,026 participants were recruited from our university, with one half used for exploratory factor analysis (EFA) to examine the factor structure of the BOSQ (sample 1) and the other half used for confirmatory factor analysis (CFA) to verify the factor structure (sample 2). In Study 2, 352 Chinese and 254 US participants were recruited to complete the BOSQ through Wenjuanxing and Amazon Mechanical Turk, enabling comparison of body odor sniffing behaviors across two cultures.

RESULTS

The Study 1 results showed that the BOSQ comprises 17 items in three factors: self-private body odor, others' body odor, and self-common body odor. The CFA results further supported that this three-factor model was a good fit. The Study 2 results showed that US participants scored higher overall and on the self-private body odor and others' body odor dimensions, whereas Chinese participants scored higher on the self-common body odor dimension.

CONCLUSIONS

The BOSQ demonstrated good reliability and validity, which is a useful tool for evaluating individuals' body odor sniffing behaviors. Cross-cultural difference existed as the US population reported a higher prevalence of body odor sniffing behavior, compared to the Chinese population.

Human odor exploration behavior is influenced by olfactory function and interest in the sense of smell

Olfaction plays an important role in social interaction. This study examined the influence of chemosensory and cognitive abilities on conscious odor sniffing behaviors in humans. Participants (N = 349) were surveyed using a questionnaire for the frequency of behaviors in terms of odor exploration from intrinsic and external sources. Chemosensory functions (e.g., odor identification, trigeminal sensitivity, taste functions, and nasal patency), self-reported olfactory function, and the subjective importance of olfaction were assessed. Hierarchical regression analyses demonstrate a strong impact of olfactory importance on odor exploration behavior. Both female gender and chemosensory function (odor identification ability and trigeminal sensitivity) had a positive impact on odor exploration behavior from individuals' own body and from external sources. Moreover, participants with dysosmia compared to those with normosmia showed less frequent odor exploration behaviors, while their behaviors were partly predicted by nasal patency. In conclusion, conscious olfactory exploration behaviors reflect the interest in the sense of smell and is strongly modulated by chemosensory function. In turn, individuals with lower olfactory sensitivity invest less in olfactory explorations.

International consensus statement on allergy and rhinology: Olfaction

BACKGROUND

The literature regarding clinical olfaction, olfactory loss, and olfactory dysfunction has expanded rapidly over the past two decades, with an exponential rise in the past year. There is substantial variability in the quality of this literature and a need to consolidate and critically review the evidence. It is with that aim that we have gathered experts from around the world to produce this International Consensus on Allergy and Rhinology: Olfaction (ICAR:O).

METHODS

Using previously described methodology, specific topics were developed relating to olfaction. Each topic was assigned a literature review, evidence-based review, or evidence-based review with recommendations format as dictated by available evidence and scope within the ICAR:O document. Following iterative reviews of each topic, the ICAR:O document was integrated and reviewed by all authors for final consensus.

RESULTS

The ICAR:O document reviews nearly 100 separate topics within the realm of olfaction, including diagnosis, epidemiology, disease burden, diagnosis, testing, etiology, treatment, and associated pathologies.

CONCLUSION

This critical review of the existing clinical olfaction literature provides much needed insight and clarity into the evaluation, diagnosis, and treatment of patients with olfactory dysfunction, while also clearly delineating gaps in our knowledge and evidence base that we should investigate further.

From musk to body odor: Decoding olfaction through genetic variation

The olfactory system combines input from multiple receptor types to represent odor information, but there are few explicit examples relating olfactory receptor (OR) activity patterns to odor perception. To uncover these relationships, we performed genome-wide scans on odor-perception phenotypes for ten odors in 1000 Han Chinese and validated results for six of these odors in an ethnically diverse population (n = 364). In both populations, consistent with previous studies, we replicated three previously reported associations (β-ionone/OR5A1, androstenone/OR7D4, cis-3-hexen-1-ol/OR2J3 LD-band), but not for odors containing aldehydes, suggesting that olfactory phenotype/genotype studies are robust across populations. Two novel associations between an OR and odor perception contribute to our understanding of olfactory coding. First, we found a SNP in OR51B2 that associated with trans-3-methyl-2-hexenoic acid, a key component of human underarm odor. Second, we found two linked SNPs associated with the musk Galaxolide in a novel musk receptor, OR4D6, which is also the first human OR shown to drive specific anosmia to a musk compound. We noticed that SNPs detected for odor intensity were enriched with amino acid substitutions, implying functional changes of odor receptors. Furthermore, we also found that the derived alleles of the SNPs tend to be associated with reduced odor intensity, supporting the hypothesis that the primate olfactory gene repertoire has degenerated over time. This study provides information about coding for human body odor, and gives us insight into broader mechanisms of olfactory coding, such as how differential OR activation can converge on a similar percept.

The social odor scale: Development and initial validation of a new scale for the assessment of social odor awareness

The degree of attention individuals pay to olfactory cues (called odor awareness) influences the role of odors in everyday life. Particularly, odors produced by the human body (i.e., social odors) are able to carry a wide variety of information and to elicit a broad spectrum of emotional reactions, making them essential in interpersonal relationships. Hence, despite the assessment of awareness toward social odors is crucial, a proper tool is still lacking. Here, we designed and initially validated the Social Odor Scale (SOS), a 12-item scale designed to measure the individual differences in awareness towards different social odors. In Study 1, an exploratory factor analysis (EFA; KMO test: MSA = 0.78; Bartlett's test: χ2(78) = 631.34, p < 0.001; Chi-squared test: χ2(42) = 71.84, p = 0.003) suggests that the three factors structure was the model that best fit with the Italian version of the scale. The confirmatory factor analysis (CFA) supports a second-order model with one higher-order factor representing social odor awareness in general and three lower-order factors representing familiar, romantic partner, and stranger social odors. The final version of the scale presented a good fit (RMSEA = 0.012, SRMR = 0.069, CFI = 0.998, TLI = 0.997). In Study 2, CFA was performed in the German version of the scale confirming the validity of scale structure. Study 3 and 4 revealed that SOS total score and its subscales were positively correlated with other validated olfactory scales, but not with olfactory abilities. Moreover, SOS was found to be related to the gender of the participants: women reported to be more aware to social odors and, specifically, to familiar social odors than men. Overall, the results indicated that SOS is a valid and reliable instrument to assess awareness toward social odors in everyday life.

Judgements of attractiveness of the opposite sex and nostril differences in self-rated mood: The effects of androstenol

Androstenol has been reported to influence judgements of attractiveness and to affect participants' mood. In the present study, participants were asked to sniff androstenol or a control odour (pure ethanol) unilaterally with the left or right nostril. Subsequently, they rated the attractiveness of photographs of the opposite sex and their own feelings on four mood scales. Participants rated the photographs as significantly more attractive after sniffing androstenol compared with the control odour. This did not depend upon androstenol being perceived as pleasant. Androstenol made male participants feel more lively, and both male and female participants more sexy, when sniffed through the right compared with the left nostril. Participants rated themselves as more irritable and aggressive when exposed to androstenol through the left nostril. The findings are discussed in relation to the effects of arousal on attraction and in the context of current theories of hemispheric differences in emotion.

Love Stinks: The Association between Body Odors and Romantic Relationship Commitment

Anecdotal reports indicate that women dislike their partner’s body odor (BO) during the breakdown of a relationship; however, whether disliking a partner’s BO is associated with intentions to break up has not been empirically tested. Therefore, the aim of the current study was to investigate, for the first time, whether disliking one’s partner’s BOs is associated with experiencing lower commitment to a romantic relationship. Eighty participants (48 partnered, 32 single and previously partnered) completed self-report questionnaires about their current or previous romantic relationship and the amount of exposure to—and hedonic ratings of—their current or former partner’s BOs. Olfactory function was also tested, and participants smelled and rated various pieces of clothing imbued with a stranger’s BO. The results demonstrated that for participants who had experienced a breakup, historically higher levels of relationship commitment were associated with higher hedonic ratings of a previous partner’s BOs, regardless of the type of BOs. For participants currently in a relationship, lower relationship commitment was associated with higher breakup intentions in response to smelling their partner’s BOs. These preliminary results contribute evidence for the positive association between exposure to a partner’s BOs and favorable hedonic appraisals of BOs; however, further research needs to be conducted in this area to investigate nuances. Lower levels of exposure to one’s partner’s BOs may be more indicative of relationship commitment than exposure to hedonically unpleasant BOs of one’s partner. The findings are discussed with reference to their implications for interventions in relationship breakdown.

The role of fragrance and self-esteem in perception of body odors and impressions of others

Human sweat odor serves as social communication signal for a person’s traits and emotional states. This study explored whether body odors can also communicate information about one’s self-esteem, and the role of applied fragrance in this relationship. Female participants were asked to rate self-esteem and attractiveness of different male contestants of a dating show, while being exposed to male participant’s body odors differing in self-esteem. High self-esteem sweat was rated more pleasant and less intense than low self-esteem sweat. However, there was no difference in perceived self-esteem and attractiveness of male contestants in videos, hence explicit differences in body odor did not transfer to judgments of related person characteristics. When the body odor was fragranced using a fragranced body spray, male contestants were rated as having higher self-esteem and being more attractive. The finding that body odors from male participants differing in self-esteem are rated differently and can be discriminated suggests self-esteem has distinct perceivable olfactory features, but the remaining findings imply that only fragrance affect the psychological impression someone makes. These findings are discussed in the context of the role of body odor and fragrance in human perception and social communication.

The Link between Attachment Style and Self-Reported Olfactory Ability: A Preliminary Investigation

Individuals in healthy romantic relationships gain significant benefits to their psychological wellbeing and physiological health. Notably, the majority of relationship research has focused on how adult attachment influences these relationship outcomes while the role of olfaction remains an emerging research focus. The aim of the current study was to bring together these seemingly unrelated factors–attachment and olfaction–in an online quasi-experimental design. The participants were 401 undergraduate students, predominantly females, ranging in age from 17 to 70 years. Participants completed a battery of questionnaires that evaluated their attachment tendencies, olfactory ability and experiences in romantic relationships. Results indicated that attachment insecurity, across both attachment anxiety and avoidance, was associated with decreased olfactory functioning for females. These findings provide preliminary evidence that olfaction is related to romantic relationship maintenance and suggests that body odors could be fundamental for evoking the attachment system. These findings also elicit enticing new avenues of research which can assist psychologists to provide targeted treatments to individuals with olfactory deficits and insecure attachment tendencies.

Olfaction in the Multisensory Processing of Faces: A Narrative Review of the Influence of Human Body Odors

A recent body of research has emerged regarding the interactions between olfaction and other sensory channels to process social information. The current review examines the influence of body odors on face perception, a core component of human social cognition. First, we review studies reporting how body odors interact with the perception of invariant facial information (i.e., identity, sex, attractiveness, trustworthiness, and dominance). Although we mainly focus on the influence of body odors based on axillary odor, we also review findings about specific steroids present in axillary sweat (i.e., androstenone, androstenol, androstadienone, and estratetraenol). We next survey the literature showing body odor influences on the perception of transient face properties, notably in discussing the role of body odors in facilitating or hindering the perception of emotional facial expression, in relation to competing frameworks of emotions. Finally, we discuss the developmental origins of these olfaction-to-vision influences, as an emerging literature indicates that odor cues strongly influence face perception in infants. Body odors with a high social relevance such as the odor emanating from the mother have a widespread influence on various aspects of face perception in infancy, including categorization of faces among other objects, face scanning behavior, or facial expression perception. We conclude by suggesting that the weight of olfaction might be especially strong in infancy, shaping social perception, especially in slow-maturing senses such as vision, and that this early tutoring function of olfaction spans all developmental stages to disambiguate a complex social environment by conveying key information for social interactions until adulthood.

Altered smell and taste: Anosmia, parosmia and the impact of long Covid-19

Background

Qualitative olfactory (smell) dysfunctions are a common side effect of post-viral illness and known to impact quality of life and health status. Evidence is emerging that taste and smell loss are common symptoms of Covid-19 that may emerge and persist long after initial infection. The aim of the present study was to document the impact of post Covid-19 alterations to taste and smell.

Methods

We conducted exploratory thematic analysis of user-generated text from 9000 users of the AbScent Covid-19 Smell and Taste Loss moderated Facebook support group from March 24 to 30th September 2020.

Results

Participants reported difficulty explaining and managing an altered sense of taste and smell; a lack of interpersonal and professional explanation or support; altered eating; appetite loss, weight change; loss of pleasure in food, eating and social engagement; altered intimacy and an altered relationship to self and others.

Conclusions

Our findings suggest altered taste and smell with Covid-19 may lead to severe disruption to daily living that impacts on psychological well-being, physical health, relationships and sense of self. More specifically, participants reported impacts that related to reduced desire and ability to eat and prepare food; weight gain, weight loss and nutritional insufficiency; emotional wellbeing; professional practice; intimacy and social bonding; and the disruption of people’s sense of reality and themselves. Our findings should inform further research and suggest areas for the training, assessment and treatment practices of health care professionals working with long Covid.

The Relationship Between Olfactory Function and Emotional Contagion

Introduction

Research has provided evidence for the transfer of single emotions including anger, anxiety and happiness through olfactory chemosignals, yet no work has examined the role of odour function in the aggregation of more complex emotional states or in the emotional contagion process. The aim of the present study was to ascertain whether an individual’s tendency to experience emotional aggregation was affected by objective measures of their olfactory function and subjective self-assessments of the importance of their own olfactory system.

Methods

In this study (N = 70), participant pairs were first assessed individually for olfactory threshold and odour identification, then completed the Importance of Olfaction Questionnaire. Each pair subsequently took part in two collaborative tasks. Individual emotion measures were taken before, during and after the completion of the two tasks.

Results

Multilevel structural equation modelling revealed that individuals’ within-dyad positive emotional agreement scores were associated with both their ‘importance of olfaction’ scores and their olfactory function. A significant association was also found between olfactory performance and the Importance of Olfaction scores.

Conclusions

These results provide evidence that the subjective importance an individual assigns to their sense of smell can predict their susceptibility to experience emotional aggregation during active, collaborative tasks.

Implications

The findings suggest that individuals’ tendency and capability to detect and respond to emotional chemosignals, a process required for olfactory-facilitated emotional contagion, may be affected by individual differences in olfactory function and subjective attitudes toward olfaction.

Olfactory impairment and close social relationships. A narrative review

Olfactory impairment is one of the more unique symptoms of COVID-19 infection and has therefore enjoyed increased public attention in recent months. Olfactory impairment has various implications and consequences ranging from difficulty detecting dangerous pathogens to hindering social functioning and social behaviors. We provide an overview of how olfactory impairment can impact 3 types of close social relationships: family relationships, friendships, and romantic relationships. Evidence is divided into several categories representing potential mechanisms by which olfactory impairment can impact close social relationships: bonding disruptions, decreased social support, missed group-eating experiences, hygiene concerns, and altered sexual behaviors. We conclude with a discussion of emerging future research questions.

Human olfactory dysfunction: causes and consequences

The sense of smell essentially contributes to social communication, guides nutrition behaviour and elicits avoidance towards environmental hazards. Olfactory smell impairment may hence entail severe consequences for affected individuals. Compared with sensory loss in other modalities, reduced olfactory function is often unnoticed by those affected and diagnosed late. Those patients seeking help frequently suffer from long-term impairments resulting in reduced well-being and quality of life. The current review provides an overview of aetiology, prevalence and specifics of diagnostics in acquired and congenital olfactory loss and focusses on short- and long-term consequences. Compensation strategies are elaborated, and treatment options are mentioned. Individual characteristics associated with the development of serious mental health impairment are discussed in order to help practitioners identifying populations at risk.

Chemosensory Anhedonia in Patients With Schizophrenia and Individuals With Schizotypy: A Questionnaire Study

Anhedonia, the loss or decline of the ability to enjoy pleasure, is an important clinical characteristic of schizophrenia. Schizotypal traits refer to the appearance of subclinical symptoms of schizophrenia across normal people. Still, few studies have investigated chemosensory anhedonia in schizophrenia patients and schizotypy individuals. Seventy-one schizophrenia patients (SCZ), 162 schizotypy individuals (SCT) as selected by the Schizotypal Personality Questionnaire (SPQ), and 182 healthy controls (HC) participated in our study. We used the Positive and Negative Syndrome Scale (PANSS) to measure the clinical symptoms of schizophrenia patients. All participants completed the Chemosensory Pleasure Scale (CPS), which was used to assess participants' smell and taste hedonic capacities. We found that the three groups differed in chemosensory anhedonia. The SCZ group presented more severe chemosensory anhedonia than the SCT group, and the SCT group presented more severe chemosensory anhedonia than the HC group. We also found that chemosensory hedonic capacity was negatively correlated with negative schizotypal traits in the SCT group. Our results suggested that chemosensory anhedonia is an important characteristic of schizophrenia spectrum disorders.

Interdisciplinary challenges for elucidating human olfactory attractiveness

Many species use chemicals to communicate. In humans, there is increasing evidence that chemicals conveyed by the body are extremely important in interpersonal relationships. However, many aspects of chemical communication remain to be explored to fully understand this function in humans. The aim of this article is to identify relevant challenges in this field, with a focus on human attractiveness in the context of reproduction, and to put forward roadmaps for future studies that will hopefully extend to a wider range of social interactions. The first challenge consists in not being limited to body (mal)odours from the axilla. Preliminary data on how the odour of the face and head is perceived are presented. Second, there is a crucial need to increase our knowledge of the chemical bases of human chemical communication. Third, cross-cultural approaches must not be overlooked, because they have a major input in understanding the universal and culture-specific aspects of chemical communication. Fourth, the influence of specific cultural practices such as contraceptive and fragrance use is likely to be prominent and, therefore, needs to be well described. The fifth and last challenge for research projects in this field is the integration of different disciplines such as behavioural sciences, social sciences, neurosciences and microbiology. This article is part of the Theo Murphy meeting issue 'Olfactory communication in humans'.