The Light Triad predicts Tinder use for love (long-term mating)

Looking from the bright side: The Light Triad predicts Tinder use for love. Barış Sevi, Burak Doğruyol. Journal of Social and Personal Relationships, April 22, 2020. https://doi.org/10.1177/0265407520918942

Abstract: The Dark Triad of personality has gained much attention in the literature, while the lighter side of personality has not received comparable attention. This study aimed to examine how the Light Triad of personality traits (Faith in Humanity, Humanism, and Kantianism) differs between Tinder users, and how these personality traits are related to motivations to use Tinder for short- and long-term mating. Cross-sectional data from current Tinder users (n = 130), past Tinder users (n = 56), and people who have never used Tinder (n = 121) were examined. The results revealed that compared to Tinder users, nonusers have higher scores on Kantianism, which might be related to Kantians not emphasizing attractiveness, a factor that has a role in online dating success. Further, Tinder users with higher total scores on the Light Triad were found to show higher motivation to use Tinder for long-term mating, whereas a significant relation was not found motivation to use Tinder for short-term mating. Long-term mating requires establishing a cooperative relationship with someone, and the motivation to use Tinder to find long-term mates may be due to the cooperation-promoting nature of the Light Triad.

Keywords Casual sex, Light Triad, love, mating, Tinder

Average happiness is high in modern societies & tends to rise even higher, which contradicts longstanding pessimism about modernization; also, happiness doesn't depend primarily on one’s social position

World Database of Happiness. A ‘findings archive.’ Ruut Veenhoven. Chapter prepared for Handbook of Wellbeing, Happiness and the Environment. Editors: Heinz Welsch, David Maddison and Katrin Rehdanz. Edward Elgar Publishing, 2018. https://personal.eur.nl/veenhoven/Pub2020s/2020a-full.pdf

1.2 Intriguing findings on happiness

The new line of research has produced several unexpected results, such as:

*  The majority of humanity appears to enjoy life. Unhappiness is the exception rather than the rule. This is at odds with common misery counts in the social sciences (Diener & Diener 1996).
*  Average happiness is high in modern societies and tends to rise even higher. This finding contradicts longstanding pessimism about modernization (Cummins 2000, Veenhoven 2005, Veenhoven & Hagerty 2005, Inglehart et. al. (2008).
*  In modern western nations, happiness differs little across social categories, such as rich and poor or males and females. The difference is rather in psychological competence (Headey and Wearing 1992). This result is at odds with the common notion in sociology that happiness depends primarily on one’s social position.
*  Differences in happiness within nations (as measured by standard deviations) tend to get smaller. This contradicts claims about growing inequality in modern society (Veenhoven 2002).
*  People live happier in individualistic societies such as Denmark, than in collectivistic societies such as Japan (Veenhoven 1999, Verne 2009). This contradicts the view that modern society falls short in social cohesion, such as proclaimed in books like ‘Bowling Alone’ (Putman 2000).
*  People do not live happier in welfare states than in equally rich nations where ‘father state’ is less open handed. Inequality of happiness does not appear to be smaller in welfare states either (Veenhoven 2000b). This finding conflicts with political left thinking.
*  Happiness is not just a matter of being better off than the Jones; though social comparison plays a role, it is not the whole story. This finding challenges cognitive theories of happiness and supports affective explanations (Veenhoven 1991, 1995, 2008).
*  Happiness is not very trait like; over a lifetime it appears to be quite variable. This finding does not fit the ‘set-point’ theory of happiness (Veenhoven 1994b, Ehrhardt et al. 2000, and Headey 2006).


Key words: literature review, research synthesis, methodology, research archive,
comparative analysis, happiness, life satisfaction, subjective wellbeing, quality of life,
air-pollution, economic growth

Foraging minds in modern environments: Individuals consistently displayed an enhanced memory for locations of high-calorie and savory-tasting foods

Foraging minds in modern environments: High-calorie and savory-taste biases in human food spatial memory. Rachelle de Vries, Emely de Vet, Kees de Graaf, Sanne Boesveldt. Appetite, April 22 2020, 104718, https://doi.org/10.1016/j.appet.2020.104718

Abstract: Human memory may show sensitivity to content that carried fitness-relevance throughout evolutionary history. We investigated whether biases in human food spatial memory exist and influence the eating behavior of individuals within the modern food environment. In two lab studies with distinct samples of 88 participants, individuals had to re-locate foods on a map in a computer-based spatial memory task using visual (Study 1) or olfactory (Study 2) cues that signaled sweet and savory high- and low-calorie foods. Individuals consistently displayed an enhanced memory for locations of high-calorie and savory-tasting foods – regardless of hedonic evaluations, personal experiences with foods, or the time taken to encode food locations. However, we did not find any clear effects of the high-calorie or savory-taste bias in food spatial memory on eating behavior. Findings highlight that content matters deeply for the faculty of human food spatial memory and indicate an implicit cognitive system presumably attuned to ancestral priorities of optimal foraging.

Keywords: Cognitive biasFood spatial memoryEating behaviorOptimal foraging theoryVisionOlfaction

Impatience and savoring versus dread: Asymmetries in anticipation explain consumer time preferences for positive versus negative events

Impatience and savoring versus dread: Asymmetries in anticipation explain consumer time preferences for positive versus negative events. David J. Hardisty  Elke U. Weber. Journal of Consumer Psychology, April 20 2020. https://doi.org/10.1002/jcpy.1169

Abstract: For positive experiences (e.g., when to eat a snack) consumers generally prefer to have them immediately, and for negative experiences (e.g., when to pay a bill) consumers often prefer to delay. Yet, across three studies (plus twelve supplemental studies) we find that anticipatory feelings push in the opposite direction, and do so differently for positive versus negative events, leading to different time preferences: the desire for immediate positives is stronger than the desire to delay negatives. For negative events, anticipatory utility is strongly negative, reducing the desire to delay bad things (i.e., consumers want to “get it over with” to minimize the psychological discomfort), but for positive events, overall anticipatory utility is weakly positive, and therefore does little to reduce consumers’ desire to expedite good things. This anticipatory asymmetry happens because when consumers think about a future positive event, they both enjoy imagining it (savoring) while simultaneously disliking the feeling of waiting for it (impatience), but when consumers think about a negative event, they both dislike imagining it (dread) and dislike the feeling of waiting for it. We demonstrate the managerial implications of these findings in a pair of field studies using online advertisements for retirement planning.

Climate assessments misuse scenarios due to competing demands & exploratory & policy relevant pathways, research practices that normalize careless use of scenarios in a vacuum of plausibility, & inherent complexity

Pielke, Roger and Ritchie, Justin, Systemic Misuse of Scenarios in Climate Research and Assessment (April 21, 2020). SSRN: https://ssrn.com/abstract=3581777

Abstract: Climate science research and assessments have misused scenarios for more than a decade. Symptoms of this misuse include the treatment of an unrealistic, extreme scenario as the world’s most likely future in the absence of climate policy and the illogical comparison of climate projections across inconsistent global development trajectories. Reasons why this misuse arose include (a) competing demands for scenarios from users in diverse academic disciplines that ultimately conflated exploratory and policy relevant pathways, (b) the evolving role of the Intergovernmental Panel on Climate Change – which effectively extended its mandate from literature assessment to literature coordination, (c) unforeseen consequences of employing a nuanced temporary approach to scenario development, (d) maintaining research practices that normalize careless use of scenarios in a vacuum of plausibility, and (e) the inherent complexity and technicality of scenarios in model-based research and in support of policy. As a consequence, the climate research community is presently off-track. Attempts to address scenario misuse within the community have thus far not worked. The result has been the widespread production of myopic or misleading perspectives on future climate change and climate policy. Until reform is implemented, we can expect the production of such perspectives to continue. However, because many aspects of climate change discourse are contingent on scenarios, there is considerable momentum that will make such a course correction difficult and contested - even as efforts to improve scenarios have informed research that will be included in the IPCC 6th Assessment.

Keywords: climate, scenarios, assessment, research integrity

With self-threat assuaged, similarity signals self-relevance, which draws people toward those who are similar to them despite negative characteristics

Can Bad Be Good? The Attraction of a Darker Self. Rebecca J. Krause, Derek D. Rucker. Psychological Science, April 21, 2020. https://doi.org/10.1177/0956797620909742

Abstract: To avoid threats to the self, people shun comparisons with similar—yet immoral, mentally unstable, or otherwise negatively viewed—others. Despite this prevalent perspective, we consider a contrarian question: Can people be attracted to darker versions of themselves? We propose that with self-threat assuaged, similarity signals self-relevance, which draws people toward those who are similar to them despite negative characteristics. To test this general idea, we explored a prevalent context that may offer a safe haven from self-threat: stories. Using a large-scale proprietary data set from a company with over 232,000 registered users, we demonstrated that people have a preference for villains—unambiguously negative individuals—who are similar to themselves, which suggests that people are attracted to such comparisons in everyday life. Five subsequent lab experiments (N = 1,685) demonstrated when and why similarity results in attraction toward—rather than repulsion from—negative others.

Keywords: stories, characters, similarity, interpersonal attraction, self-relevance, open data, preregistered

---
Also check When Do We Identify with the Bad Guy? https://insight.kellogg.northwestern.edu/article/identify-with-the-villain

Sexual attraction modulates interpersonal distance and approach-avoidance movements towards virtual agents in males

Sexual attraction modulates interpersonal distance and approach-avoidance movements towards virtual agents in males. Robin Welsch, Christoph von Castell, Martin Rettenberger, Daniel Turner, Heiko Hecht, Peter Fromberger. PLoS, April 21, 2020. https://doi.org/10.1371/journal.pone.0231539

Abstract: How does sexual attraction alter social interaction behavior? We examined the influence of sexual orientation on locomotor approach-avoidance behavior and interpersonal distance. We immersed androphilic and gynophilic male subjects into a virtual environment and presented various male and female virtual persons. In the first experiment, subjects took a step forward (approach) or backward (avoidance) in response to the sex of the virtual person. We measured reaction time, peak velocity, and step size, and obtained ratings of sexual attractiveness in every trial. In the second experiment, subjects had to approach the virtual person as if they were to engage in a social interaction. Here, we analyzed interpersonal distance and peak velocity of the approaches. Our results suggest that sexual attraction facilitates the approach response and reduces the preferred interpersonal distance. We discuss our findings in terms of proxemics, current findings in sex research, and the applicability of our novel task in other fields of psychological research.

Discussion

Male subjects seem to be attracted towards virtual persons who match their sexual orientation. In the AAT Experiment, subjects initiated approach movements towards avatars of their preferred sex faster than they initiated avoidance movements. No such difference was found for the non-preferred sex. Here, instructed approach and avoidance were initiated in the same manner. Subjects also made larger and faster steps in response to their preferred sex avatar. This pattern of effects can be explained when considering sexual attractiveness. The facilitation of approach steps was related to the individual degree of rated sexual attractiveness.

The IPD Experiment showed that gynophilic males preferred shorter IPDs towards female avatars as compared to male avatars, which is consistent with previous studies [e.g. 20]. However, the effect of avatar sex on IPD was considerably diminished in androphilic males. Furthermore, androphilic subjects preferred shorter overall IPDs compared to gynophilic subjects. Similarly to the sex effect on IPD, the peak velocity of the approach reaction was faster towards female avatars as compared to male avatars in gynophilic subjects. These differences were not present in androphilic subjects.

What fuels this behavior? As proposed by the Dual Control Model and related theories in sex research, sexual arousal caused by sexual attraction promotes approach tendencies (AAT Experiment), which results in shorter and more intimate conversation distances (IPD Experiment). It is remarkable that these effects do carry over to virtual avatars.

In the second Experiment, IPD varied as a function of sexual orientation when interacting with male and female virtual persons. Gynophilic subjects produced the well-known sex effect on IPD, i. e., shorter distances towards females as compared to males; interestingly, this effect was absent in androphilic subjects. The diminished sex effect on IPD in androphilic subjects could be interpreted in light of equilibrium theory [14, 21]: Sexual attraction to men promotes approach tendencies (see AAT Experiment) towards male avatars, but no avoidance towards female avatars, which merely reduces the preferred IPD to male avatars, thus resulting in equal IPD between male and female avatars. The same reasoning applies to the differential sex effect on peak velocity as effects are largely correlated within the IPD Experiment.

When correlating the step size-bias from the AAT Experiment and preferred distance from the IPD Experiment, we could find a medium-sized correlation between the two aggregates, which again strengthens the hypothesis that IPD is regulated by approach and avoidance forces [14, 21]. A recent study by Ruggiero, Rapuano [50] lends credibility to this interpretation, i.e. approach motivation promoting smaller IPD. They found that inducing warmth by holding a warm beverage, which was supposed to increase approach motivation, produced smaller IPD than did the induction of coldness.

Note that when controlling for sexual attraction, the sex effect on IPD persisted. Referring to Uzzell and Horne [17], our findings suggest that sexual orientation and thus sexual attraction may partly overshadow the sex effect on IPD. Previous studies investigating sex effects [17, 19, 20] have presented a small set of targets, have not measured explicit sexual attractiveness and sexual orientation, or did not use an immersive social interaction scenario, which limited the ability to detect sex effects on IPD and disentangle the effect from sexual attractiveness. Furthermore, although Uzzell and Horne [17] did find an effect of sexual orientation on IPD, they could not reveal any differences between androphilic and gynophilic men, probably due to low statistical power and experimental control. Therefore, our study can be considered the first study to show an interaction of sexual orientation and sex of the approached person on IPD in men. Our study can also reveal why sex effects on IPD tend to be heterogeneous. Sexual attractiveness can serve as an important determinant of IPD and may therefore override sex effects. As this depends on the degree of attractiveness, it could explain the heterogeneous results across studies, e.g. when a confederate is particularly attractive in a social interaction task measuring IPD and/or when androphilic subjects make up a proportion of the sample.

Note also that we did not expect on overall difference in IPD between gynophilic and androphilic male subjects. This is in line with Uzzell and Horne [17] who report an overall similar pattern of IPD preferences in their observational study (gynophilic > androphilic males; by about 6 cm). Thus, this difference in preferred IPD between androphilic and gynophilic male subjects deserves to be further investigated with a larger sample powered to study overall between-subjects variability.

This is the first study to investigate a whole-body approach and avoidance movements within a virtual environment. The AAT reliably detected effects on different sets of measurements and converged with the results in the IPD Experiment. Furthermore, we found effects on a range of dependent variables, which adds credibility to the smaller effects found in previous AAT studies [7, 10]. These results indicate that the AAT in combination with the IPD-paradigm may be more ecologically valid than alternative approaches used in previous studies (e. g., using 2D-stimuli and arm-movements). Thus, we believe that these tasks may also be useful in other fields of research with a focus on approach/avoidance-behavior, such as social interaction behavior in psychopathology or forensic research.

In the domain of sex research, our data provide further evidence for the assumption that sexually arousing stimuli do not solely activate sexually specific motor responses but also general locomotor approach behavior [51]. We found that sexually relevant stimuli affect IPD in virtual social encounters. Thus, we assume that the propensity of reacting on stimuli perceived as sexually relevant may influence our every-day social interaction behavior. In this regard, our study points to the potential of using VEs within sex research. Contrary to previous research, we could observe social interaction behavior with respect to sexual attraction in an ecologically more valid and highly controlled fashion. Subjects were instructed to approach a virtual person as if they wanted to ask for directions, which is potentially more ecologically valid than current explicit and implicit measures of sexual interest [for an overview see 52]. For viewing time, an implicit measure of sexual interest, it has already been shown that presenting virtual characters in highly immersive environments can enhance the discriminative validity of viewing time [33].

These findings are also potentially useful for forensic psychology. Sexual motivation is a key component in recent models of sexual offense behavior [53–56]. Our results may be applied to a sample of people who have sexually offended, in order to measure the strength of their approach reaction and to distinguish approach- vs. avoidance-oriented individuals who have committed sexual offenses, to allocate treatment resources more appropriately and efficiently. Some limitations must be considered with reference to our sample and to our method. First, we have only studied male western subjects. Future studies should replicate our findings in a female sample and include non-western subjects. This is particularly important considering the variation between nationalities [29, 30] which could potentially slightly enhance or diminish the sex effect on IPD. Second, we have not controlled for sexual identity [17]. Masculinity or femininity could also influence the sex effect on IPD.

Third, we have confronted subjects with a larger number of trials in a relatively small amount of time (230 trials in 90 minutes). We have also administered the experiments in a fixed order. The IPD Experiment was always followed by the AAT Experiment to minimize potential effects of familiarity in the IPD Experiment. Both factors could have contributed to fatigue, habituation to the stimuli as well as exhaustion due to our request for rapid stepping movement, especially in the AAT Experiment. This could reduce the magnitude of the effects and should be considered in future studies as a possible enhancement. We hypothesize that a randomized order will not change the direction of the reported effects, which may be evaluated in future studies with larger samples. Still, before application of the AAT or the IPD-paradigm in applied forensic contexts, the length of data collection as well as the task demands should be carefully evaluated and reduced. Fourth, administering the AAT in a virtual environment is a new measure that deserves further investigation in terms of reliability and validity.

In conclusion, the recording of IPD-regulation and the approach-avoidance scenario, both implemented in a virtual environment, provide a powerful and rather implicit paradigm to study the effects of sexual attractiveness on behavioral propensities.

The majority of studies, & especially the higher quality studies, showed that those who avoided meat consumption had significantly higher rates or risk of depression, anxiety, or self-harm behaviors

Meat and mental health: a systematic review of meat abstention and depression, anxiety, and related phenomena. Urska Dobersek et al. Critical Reviews in Food Science and Nutrition, Apr 20 2020. https://doi.org/10.1080/10408398.2020.1741505

Abstract
Objective: To examine the relation between the consumption or avoidance of meat and psychological health and well-being.

Methods: A systematic search of online databases (PubMed, PsycINFO, CINAHL Plus, Medline, and Cochrane Library) was conducted for primary research examining psychological health in meat-consumers and meat-abstainers. Inclusion criteria were the provision of a clear distinction between meat-consumers and meat-abstainers, and data on factors related to psychological health. Studies examining meat consumption as a continuous or multi-level variable were excluded. Summary data were compiled, and qualitative analyses of methodologic rigor were conducted. The main outcome was the disparity in the prevalence of depression, anxiety, and related conditions in meat-consumers versus meat-abstainers. Secondary outcomes included mood and self-harm behaviors.

Results: Eighteen studies met the inclusion/exclusion criteria; representing 160,257 participants (85,843 females and 73,232 males) with 149,559 meat-consumers and 8584 meat-abstainers (11 to 96 years) from multiple geographic regions. Analysis of methodologic rigor revealed that the studies ranged from low to severe risk of bias with high to very low confidence in results. Eleven of the 18 studies demonstrated that meat-abstention was associated with poorer psychological health, four studies were equivocal, and three showed that meat-abstainers had better outcomes. The most rigorous studies demonstrated that the prevalence or risk of depression and/or anxiety were significantly greater in participants who avoided meat consumption.

Conclusion: Studies examining the relation between the consumption or avoidance of meat and psychological health varied substantially in methodologic rigor, validity of interpretation, and confidence in results. The majority of studies, and especially the higher quality studies, showed that those who avoided meat consumption had significantly higher rates or risk of depression, anxiety, and/or self-harm behaviors. There was mixed evidence for temporal relations, but study designs and a lack of rigor precluded inferences of causal relations. Our study does not support meat avoidance as a strategy to benefit psychological health.

Keywords: Anxiety, depression, meat, mental health, self-harm, vegan, vegetarianism

Discussion

Based on this systematic review comprising 160,257 participants from varied geographic regions, including Europe, Asia, North America, and Oceania, aged 11 to 96 years, there is clear evidence that meat-abstention is associated with higher rates or risk of depression, anxiety, and self-harm. The results with respect to mood states, affective well-being, stress perception and QoL are less clear and the majority of studies do not support unequivocal inferences.

Across all studies, there was no evidence to support a causal relation between the consumption or avoidance of meat and any psychological outcomes. However, three studies provided evidence suggesting (contradictory) temporal relations between meat-abstention and depression and anxiety. Michalak, Zhang, and Jacobi (2012) demonstrated that the mean age at the adoption of meat-abstention (30.58 years) was substantially older than the mean age of the onset of metal disorder (24.69 years). These authors posited that mental disorders may lead to the adoption of a meat-less diet. The authors stated that individuals with mental disorders may “choose a vegetarian diet as a form of safety or self-protective behavior” (Michalak, Zhang, and Jacobi 2012, 6) due to the perception that plant-based diets are more healthful or because individuals with mental disorders may be “more aware of suffering of animals” (Michalak, Zhang, and Jacobi 2012, 2). Interestingly, these investigators also found that people with a lifetime diagnosis of psychological disorders consumed less fish and fast food. While these results conflict with previous research on fast food and mental health (Crawford et al. 2011), they support Matta et al.’s results and hypothesis that the exclusion of any food group, and especially meat and poultry, is associated with increased odds of having symptoms of psychological disorders (Matta et al. 2018).

Conversely, in their longitudinal analysis, Lavallee et al. (2019) found that meat-abstention was linked to “slight increases over time” (Lavallee et al. 2019, 153) in depression and anxiety in Chinese students. One important caveat when considering these disparate results on temporal relations may be differences in the factors that led to meat-abstention (e.g., religious practices, health and ethical considerations, or socio-economic status). For example, economically disadvantaged individuals who do not consume meat due to its relative cost may be at risk for ill-health for myriad reasons independent of their lack of meat consumption. Thus, future research examining temporal relations should establish clear distinctions between individuals and populations that abstain from meat consumption due to ethical, religious, and health-related perceptions, or those who do not consume meat for economic reasons.

Strengths, limitations, and flaws of the extant literature

Psychological outcomes

The most rigorous studies used objective and/or multiple assessments of psychological outcomes. For example, Michalak, Zhang, and Jacobi (2012) were the first investigators to use standardized and comprehensive assessment of mental disorders based on DSM criteria (APA 2013). Similarly, Baines, Powers, and Brown (2007) provided multiple assessments of psychological outcomes that included reported physician-diagnosed conditions, and the use of prescription medication for depression and anxiety in concert with self-reported symptoms and behaviors (e.g., self-harm; Baines, Powers, and Brown 2007). Comparably, Hibbeln et al. (2018) included detailed participant histories, including childhood contact with psychiatric services and family history of depression. Methodologically weaker studies employed a single questionnaire and, in some cases, employed a single-item examining psychological symptoms over a limited timeframe (e.g., the previous week).

Sampling

The most rigorous studies examined large, representative and/or matched samples (Baines, Powers, and Brown 2007; Matta et al. 2018; Michalak, Zhang, and Jacobi 2012), whereas the least rigorous used biased recruitment strategies and biased convenience sampling. For example, Michalak, Zhang, and Jacobi (2012) employed both a large representative sample and a socio-demographically matched subsample for comparison. The strength of this approach cannot be understated. Similarly, Neumark-Sztainer et al. (1997) employed a matched sample drawn from a much larger study population. Conversely, a number of studies attempted to over-sample vegans and vegetarians by directly targeting these groups via internet sources such as “social websites geared to VG and VEG [vegan and vegetarians]”(Beezhold et al. 2015) and vegan chat-rooms and/or magazines and vegetarian “fairs” (Boldt et al. 2018; Wirnitzer et al. 2018). As discussed below, these sampling strategies in concert with self-reported data are a major design flaw.

Investigators who seek to over-sample groups that are highly invested (e.g., ethically, socially, intellectually or emotionally) in their “lifestyle” or dietary choices should acquaint themselves with the large body of research on cognitive dissonance (Festinger 1962), social-desirability (Fisher 1993), and observer-expectancy effects (e.g., reactivity). This body of work is especially relevant when applied to the errors and biases of self-reported dietary intake data; for details, please see (Archer, Hand, and Blair 2013; Archer, Lavie, and Hill 2018b; Archer, Marlow, and Lavie 2018c, 2018d; Archer, Pavela, and Lavie 2015; Hebert et al. 1995; Schoeller et al. 2013). This large and well-established body of research suggests that for individuals who maintain a strong group identity or affinity, meat consumption or avoidance may represent a significant ethical, intellectual, emotional, behavioral, social and/or spiritual investment that extends well-beyond a simple dietary choice. As such, many individuals (e.g., Paleo and “meat-only” dieters, vegans, vegetarians, Seventh Day Adventists) will be pre-disposed to report significantly higher levels of physical and psychological health to avoid cognitive dissonance and remain consistent with self- and/or group-appraisals.

These non-intentional biases in concert with the potential for a participant to intentionally misreport outcomes to support his or her ideological stances or religious beliefs may induce systematic and non-quantifiable errors when employing self-report protocols. As such, the oversampling of groups that are highly invested in their dietary regimes for health, religious, or ideologic concerns (e.g., animals rights) will lead to biased recruitment and extremely unreliable data. In fact, research on cognitive dissonance and social desirability suggests that the greater the motivation for adhering to one’s dietary or lifestyle pattern (or self-conception), the larger the potential error induced via the use of self-reports (Archer, Marlow, and Lavie 2018c; Festinger 1962). Future studies should employ objective data collection protocols when over-sampling groups that may be prone to intentional and/or non-intentional misreporting.

Assessment of dietary status (exposure)

One major limitation of all studies in this review was the use of self-reported dietary status. Currently, there is an escalating and contentious debate on the validity of self-reported dietary data and the use of food frequency questionnaires in nutrition (Archer and Lavie 2019b; Archer, Lavie, and Hill 2018b; Archer, Marlow, and Lavie 2018d; Archer, Pavela, and Lavie 2015; Ioannidis 2018; Martín-Calvo and Martínez-González 2018; Satija et al. 2015; Schoeller et al. 2013; Subar et al. 2015; Trepanowski and Ioannidis 2018). The debate revolves around two major criticisms. First, critics of self-reported data state that without objective corroboration of dietary self-reports, it is impossible to quantify measurement error due to intentional and nonintentional distorting factors, such as deliberate misreporting (i.e., deception/lying), social desirability, reactivity, misestimation, and false memories of dietary intake (Archer, Pavela, and Lavie 2015). Second, critics argue that pseudo-quantification (i.e., the transformation of reported foods and beverages into estimates of nutrient and caloric intake) created a fictional discourse on diet-disease relations (Archer, Hand, and Blair 2013; Archer, Lavie, and Hill 2018b). This latter argument is based on the fact that ∼65% of self-reported dietary data have been shown to be physiologically implausible [i.e., respondents cannot survive on the amount of foods and beverages reported (Archer, Hand, and Blair 2013; Archer, Pavela, and Lavie 2015; Ferrari et al. 2002; Goldberg et al. 1991)].

The first criticism is potentially applicable to our analyses. Nevertheless, the dichotomous nature of our classifications (i.e., meat-consumers versus meat-abstainers) reduces both its importance and impact. The second critique regarding pseudo-quantification is not relevant to our review, nor is it relevant to qualitative assessments of dietary intake.

Duration of dietary patterns

A number of studies failed to include information of the age at which meat-abstention began or the duration of non-consumption. If a relationship exists between the length of time an individual has abstained from meat consumption and physical or psychological health, these data are essential to future investigations. This is especially true since the nutritional deficiencies that are sometimes associated with veganism and vegetarianism may be more detrimental in children and adolescents (Cofnas 2019) and may take years to develop (Craig 2010; Dwyer 1991).

Other potential confounders

Clearly, diet is not the only determinant of psychological health (Archer 2018a, 2018b). Nevertheless, a number of the studies failed to include important potential confounders and effect modifiers. These include race, ethnic, or religious affiliation, social norms, as well as lifestyle behaviors that directly affect health (e.g., smoking, and alcohol use) and the physiologic determinants of dietary energy intake (e.g., physical activity, body cellularity; Archer 2018b; Archer, Lavie, and Hill 2018a; Archer et al. 2018e). Given that when compared to the general population, individuals who follow a vegetarian diet tend to be more health-conscious, more physically active, more highly educated, consume less alcohol, be nonsmokers and have higher socio-economic status (Appleby et al. 2016; Appleby and Key 2016; Chang-Claude et al. 2005), it is essential for future studies to include detailed information on participants’ health and behavioral histories and current characteristics.

Strengths and limitations of this review

This systematic review had several strengths, including our a priori decision to select only studies that provided a clear distinction between meat-consumers and meat-abstainers. This decision allowed for a clear and yet rigorous assessment. While myriad studies examined vegetarianism along a continuum, these were excluded simply because the lack of a clear distinction rendered inferences equivocal.

A second strength was our decision to limit our primary outcomes to well-defined mental disorders (i.e., depression, anxiety, and related symptoms) and a limited number of secondary outcomes (e.g., self-harm). This focus allowed for a concise yet rigorous review and ameliorated the effects of poorly operationalized psychological phenomena. For example, by excluding results on disordered eating, dietary restraint, orthorexia, and personality (e.g., neuroticism), we avoided the potential misclassification and concomitant pathologizing of those who simply wish to avoid specific foods or food groups (e.g., vegans).

Our study also had limitations. First, we excluded non-English language studies, that could potentially bias our results in favor of “Western” norms which include meat consumption. For example, our selection criteria excluded papers published in languages other than English. (e.g., Japanese, Hindi) and in non-English databases. Thus, our review may have omitted studies from geographic regions that follow predominantly vegetarian or plant-based dietary patterns. In these areas, the relation between meat-avoidance and psychological health may differ from “Western” nations. Nevertheless, our review included a large sample from China; so, this limitation may be trivial.

Second, while our search was clearly defined and comprehensive, our criteria excluded a large number of papers that provided data on this topic [e.g., see (Anderson et al. 2019; Barthels, Meyer, and Pietrowsky 2018; Burkert et al. 2014a; Cooper, Wise, and Mann 1985; Jacka et al. 2012; Larsson et al. 2002; Li et al. 2019; Northstone, Joinson, and Emmett 2018)]. Nevertheless, we think that a highly focused review has the potential to provide stronger evidence and, as such is more informative to the medical, research, and lay communities. Third, despite the high confidence we place in our finding that meat-abstention is linked to psychological disorders, study designs and lack of rigor precluded valid inferences of temporality and causality.

Fourth, meat consumption is often inconsistently classified in research and national surveillance settings (Gifford et al. 2017; O’Connor et al. 2020) as well as across languages. For example, in English, the broad category of “meat” subsumes both “red” and “white” meat (e.g., beef and poultry). However, in German, the term “meat” excludes poultry. As such, the results for the studies employing German samples were potentially more restrictive. Finally, inferences from our results are only as accurate as the data collected by the included studies. Given that all studies relied on self-reported dietary status, there is the possibility of misclassification because self-reported dietary consumption is not the equivalent of actual dietary consumption (Archer, Hand, and Blair 2013; Archer, Lavie, and Hill 2018b; Archer, Marlow, and Lavie 2018c, 2018d; Archer, Pavela, and Lavie 2015). In other words, there is an obvious and important distinction between merely reporting that one avoids meat and actual meat-abstention; and research supports the fact that self-defined vegetarians and meat-abstainers may consume meat (Haddad and Tanzman 2003).

Suggestions for future direction

Future investigators should avoid the most common flaws detailed herein (e.g., uncorroborated self-reported data, biased sampling, confounding, etc.). First, the limitations of self-reported dietary data may be partially overcome with point-of-purchase (barcode) data (Ng and Popkin 2012). Nevertheless, while purchase data may be more objective, it is not necessarily an accurate proxy for actual consumption. Second, investigators must acknowledge and address the effects of biased sampling with the use of self-reported data. Individuals highly invested in specific dietary patterns may be predisposed to intentional and non-intentional misreporting. Third, detailed behavioral and health-related histories and current lifestyles should be considered essential. The use of physician-diagnosed disorders based on criteria from the DSM-V (APA 2013) is preferable to self-reported symptoms and would assist in producing more definitive results.

Given the results of this review, an interesting future direction would be to examine if meat consumption per se has psychological benefits. For example, there is evidence that a significant number of vegans and vegetarians return to meat consumption over time and that former vegetarians and vegans in the U.S. outnumber current meat-abstainers (Faunalytics 2016). As such, one research question that can be answered empirically is whether it is the nutritional properties of meat (as measured via serum biochemical analyses), the reduced social burden or stigma associated with omnivory, or other physiologic or social factors that drive the transition from meat-abstainer back to meat-consumer.

Bilingualism Affords No General Cognitive Advantages: A Population Study of Executive Function in 11,000 People

Bilingualism Affords No General Cognitive Advantages: A Population Study of Executive Function in 11,000 People. Emily S. Nichols et al. Psychological Science, April 20, 2020. https://doi.org/10.1177/0956797620903113

Abstract: Whether acquiring a second language affords any general advantages to executive function has been a matter of fierce scientific debate for decades. If being bilingual does have benefits over and above the broader social, employment, and lifestyle gains that are available to speakers of a second language, then it should manifest as a cognitive advantage in the general population of bilinguals. We assessed 11,041 participants on a broad battery of 12 executive tasks whose functional and neural properties have been well described. Bilinguals showed an advantage over monolinguals on only one test (whereas monolinguals performed better on four tests), and these effects all disappeared when the groups were matched to remove potentially confounding factors. In any case, the size of the positive bilingual effect in the unmatched groups was so small that it would likely have a negligible impact on the cognitive performance of any individual.

Keywords: bilingualism, executive function, cognition, aging, null-hypothesis testing

Discrimination in Harvard Admissions: Asian Americans would be admitted at a rate 19% higher absent discrimination

Asian American Discrimination in Harvard Admissions. Peter Arcidiacono Josh Kinsler Tyler Ransom. April 20, 2020. http://public.econ.duke.edu/~psarcidi/realpenalty.pdf

Abstract: Detecting racial discrimination using observational data is challenging because of the presence of unobservables that may be correlated with race. Using data made public in the SFFA v. Harvard case, we estimate discrimination in a setting where this concern is mitigated. Namely, we show that there is a substantial penalty against Asian Americans in admissions with limited scope for omitted variables to overturn the result. This is because (i) Asian Americans are substantially stronger than whites on the observables associated with admissions and (ii) the richness of the data yields a model that predicts admissions extremely well. Our preferred model shows that Asian Americans would be admitted at a rate 19% higher absent this penalty. Controlling for one of the primary channels through which Asian American applicants are discriminated against—the personal rating—cuts the Asian American penalty by less than half, still leaving a substantial penalty.

Cognitive sophistication (indexed by analytic thinking, numeracy, basic science knowledge, and bullshit skepticism) was a negative predictor of COVID-19 misperceptions

Pennycook, Gordon, Jonathon McPhetres, Bence Bago, and David G. Rand. 2020. “Predictors of Attitudes and Misperceptions About COVID-19 in Canada, the U.K., and the U.S.A.” PsyArXiv. April 14. doi:10.31234/osf.io/zhjkp

Abstract: The COVID-19 pandemic presents an unprecedented challenge to humanity. Yet there seems to be substantial variation across individuals in knowledge and concern about COVID-19, as well as in the willingness to change behaviors in the face of the pandemic. Here, we investigated the roles of political ideology and cognitive sophistication in explaining these differences across the U.S.A. (N = 689), the U.K. (N = 642), and Canada (N = 644) using preregistered surveys conducted in late March, 2020. We found evidence that political polarization around COVID-19 risk perceptions, behavior change intentions, and misperceptions was greater in the U.S. than in the U.K.. However, Canada and the U.S. did not strongly differ in their level of polarization. Furthermore, in all three countries, cognitive sophistication (indexed by analytic thinking, numeracy, basic science knowledge, and bullshit skepticism) was a negative predictor of COVID-19 misperceptions – and in fact was a stronger predictor of misperceptions than political ideology (despite being unrelated to risk perceptions or behavior change intentions). Finally, we found no evidence that cognitive sophistication was associated with increased polarization for any of our COVID-19 measures. Thus, although there is some evidence for political polarization of COVID-19 in the U.S. and Canada (but not the U.K.), accurate beliefs about COVID-19 (albeit not intentions to act) are broadly associated with the quality of one’s reasoning skill regardless of political ideology or background polarization.

We tend to overstate the improvement in well-being over time and to understate past happiness; it thus seems that feeling happy today implies feeling better than yesterday

Alberto Prati, Claudia Senik. Feeling good or feeling better?. 2020. ffhalshs-02545228f

Abstract: Can people remember correctly their past well-being? We study three national surveys of the British, German and French population, where more than 50,000 European citizens were asked questions about their current and past life satisfaction. We uncover systematic biases in recalled subjective well-being: on average, people tend to overstate the improvement in their well-being over time and to understate their past happiness. But this aggregate figure hides a deep asymmetry: while happy people recall the evolution of their life to be better than it was, unhappy ones tend to exaggerate its worsening. It thus seems that feeling happy today implies feeling better than yesterday. These results offer an explanation of why happy people are more optimistic, perceive risks to be lower and are more open to new experiences.

Keywords: life satisfaction; remembered utility, memory biases; intra-personal comparisons.
JEL: I31, D91

Gullibility impressions are based on cues linked to low levels of perceived threat, like babyfacedness & smiles, making judgments based on perceived harmlessness (i.e., positive intentions & low capabilities)

Jaeger, Bastian, and Erdem O. Meral. 2020. “Who Can Be Fooled? Modeling Perceptions of Gullibility from Facial Appearance.” PsyArXiv. April 14. doi:10.31234/osf.io/vw79y

Abstract: In many situations, ranging from cooperative exchange to fraud, people are faced with the challenge to judge how trusting or naïve (i.e., gullible) others are. In three studies, using both theory-driven and data-driven methods, we examine how people form gullibility judgments based on a person’s facial appearance. People have a shared representation of what a gullible person looks like. Gullibility impressions are positively related to trustworthiness impressions, but negatively related to dominance impressions (Study 1, n = 254). Examining the influence of a wide range of facial characteristics, we find that gullibility impressions are based on cues that have been linked to low levels of perceived threat, such as babyfacedness (Study 2, n = 403) and smiles (Study 3, n = 209). Together, these findings show that people form gullibility judgments based on facial cues that are seen as indicators of relative harmlessness (i.e., positive intentions and low capabilities).

The presence of sex differences in social cognition is controversial; these authors found no significant sex differences in most of social cognition tasks; conversely, women reported higher scores on empathy

Social cognition and sex: Are men and women really different? Marialaura Di Tella, Francesca Miti, Rita B. Ardito, Mauro Adenzato. Personality and Individual Differences, Volume 162, 1 August 2020, 110045. https://doi.org/10.1016/j.paid.2020.110045

Highlights
• The presence of sex differences in social cognition is controversial.
• Several social cognition measures were administrated to 210 healthy participants.
• Participants were equally divided between men and women.
• No significant sex differences were found in most of social cognition tasks.
• Conversely, women reported higher scores on empathy than men.

Abstract: Social cognition includes the ability to represent other people's intentions and beliefs, and the ability to share and recognise the emotions of others. Here, the main aim was to assess the possible presence of sex differences across four aspects of social cognition: (1) recognition of dynamic facial expressions; (2) representation of other people's mental states (both affective and cognitive Theory of Mind, ToM); (3) empathy; (4) identification and regulation of one's own emotions. Measures assessing social cognition were administrated to two hundred ten participants equally divided between men and women. Results showed no significant sex differences in affective and cognitive ToM, in the recognition of emotional facial expressions (with the exception of anger: women were more accurate than men), and in the ability to identify and regulate one's own emotions. A different result was found for empathy, with women reporting higher scores than men. No significant differences between women during follicular vs. luteal phase of menstrual cycle for all the social cognition measures were found. These results are discussed in light of the existing literature. To our knowledge, this study represents one of the few attempts to analyse in a single work sex differences across multiple areas of social cognition.

Keywords: Emotion recognitionEmotional functioningEmpathySex differencesSocial cognitionTheory of Mind

Disgust-sensitive people find little similarity between themselves and strangers; pathogen disgust predicts similarity perceptions beyond sexual and moral disgust

We're not of the same feather: Disgust sensitivity and reduced perceived similarity to unknown others. Sari Mentser, Ravit Nussinson. Personality and Individual Differences, Volume 163, 1 September 2020, 110039. https://doi.org/10.1016/j.paid.2020.110039

Highlights
• Disgust-sensitive people find little similarity between themselves and strangers
• Pathogen disgust predicts similarity perceptions beyond sexual and moral disgust
• The threat of pathogens is linked with increased perceived social distance

Abstract: Perceptions of interpersonal similarity are accompanied by attraction and bonding, often leading to physical contact. Given that physical proximity to social beings increases the odds of catching infectious diseases, we propose a reverse relationship, whereby sensitivity to the presence of pathogens results in perceiving unfamiliar others as less similar to oneself. Four studies involving 980 participants and operationalizing others in three different ways confirm that individual differences in propensity to feel disgust (i.e., react emotionally to potential sources of pathogens in the environment) are associated with perceptions of interpersonal similarity to strangers. Study 1 showed that individuals who score higher in disgust sensitivity perceive themselves as less psychologically similar to visually displayed social targets. Study 2, using vague descriptions of hypothetical figures, found that high-disgust-sensitivity participants tend to assume that others' personal preferences contrast with their own. Study 3 demonstrated that the disgust–dissimilarity association holds for prototypical members of social groups. Finally, Study 4 confirmed that this link reflects pathogen-related (above and beyond sexual or moral) disgust. In all studies, controlling for participants' gender, religiosity, and illness recency did not change the results. We discuss our findings and propose novel directions for future research.

Keywords: Disgust sensitivityPathogen threatBehavioral immune systemInterpersonal similarity

Losing stinks! The effect of competition outcome on body odour quality

Losing stinks! The effect of competition outcome on body odour quality. Jitka Fialová, Vít Třebický, Radim Kuba, David Stella, Jakub Binter and Jan Havlíček. Philosophical Transactions of the Royal Society B: Biological Sciences, Apr 20 2020. https://doi.org/10.1098/rstb.2019.0267

Abstract: Dominance hierarchy is often established via repeated agonistic encounters where consistent winners are considered dominant. Human body odour contains cues to psychological dominance and competition, but it is not known whether competition outcome (a marker of a change in dominance hierarchy) affects the hedonic quality of human axillary odour. Therefore, we investigated the effect of winning and losing on odour quality. We collected odour samples from Mixed Martial Arts fighters approximately 1 h before and immediately after a match. Raters then assessed samples for pleasantness, attractiveness, masculinity and intensity. We also obtained data on donors' affective state and cortisol and testosterone levels, since these are known to be associated with competition and body odour quality. Perceived body odour pleasantness, attractiveness and intensity significantly decreased while masculinity increased after a match irrespective of the outcome. Nonetheless, losing a match affected the pleasantness of body odour more profoundly, though bordering formal level of significance. Moreover, a path analysis revealed that match loss led to a decrease in odour attractiveness, which was mediated by participants’ negative affective states. Our study suggests that physical competition and to some extent also its outcome affect the perceived quality of human body odour in specific real-life settings, thus providing cues to dominance-related characteristics.

5. Discussion

In this study, we tested the effect of winning and losing a physical confrontation on human body odour quality and investigated factors that may mediate observed changes. We expected that winning would have a positive effect on body odour quality and losing a negative effect on it. We also predicted that winning would be associated with positive affective states, a rise in T levels and decrease in C levels, while losing would be characterized by the opposite pattern. Moreover, we hypothesized that these factors would mediate a change in body odour quality.

We found that after a match, perceived odour pleasantness, attractiveness and intensity significantly decreased, while masculinity increased in both winners and losers. Nevertheless, the decrease in pleasantness was more pronounced in losers, which suggests that losing has a more negative effect on body odour quality. We found no statistically significant differences in body odour ratings between winners and losers either before or after a match. Path analysis showed that a loss led to a decrease in odour attractiveness and this effect was mediated by participants' negative emotions.

Winning a match may entail a rise in the dominance hierarchy, while losing lowers the rank: in our case, the match score was added to a personal profile, which affects the league rank. Both losing and winning have consequences for both competitors. Nonetheless, the relatively more profound odour changes in losers suggest that losing may be perceived as having more serious consequences because it may be linked not only to lower league ranking but also to more or less serious injuries. In ring-tailed lemurs (Lemur catta), injury affects the chemical composition of secretion and injury status can be discerned by other individuals [86,87]. Similarly, it could be expected that fighters who lost suffered more injuries during a match and that might be reflected in their body odour. In our study, however, that does not seem to be the case since self-assessed pain did not significantly differ between winners and losers and it was not associated with any of the rated odour characteristics.

Our results thus indicate that competitive situations per se can have an effect on body odour, because after a match, while masculinity increased, both pleasantness and attractiveness decreased. The influence of competition on body odour has been demonstrated already by Adolph et al. [37], although they found that the tested odour samples affected exposed individuals on a subliminal level without any perceived differences between competition-linked and control odours. In our study, the perceived odour quality changed, which could be linked to increased sweating owing to the physical effort during the match. Thermoregulation involves mainly eccrine glands [88], which during exertion produce more diluted, watery, and less oily secretion consisting mostly of water and electrolytes derived from blood plasma and sodium chloride [89]. The change in odour quality we observed could thus be owing to the different quality of sweat. This finding should raise caution with respect to using sports odours as control stimuli (e.g. [90,91]), because they may have somewhat different properties than for example odours collected during sleep (e.g. [83]).

(a) Link between dominance and body odour

The results of some animal studies suggest dominant individuals may have specific intrinsic odour qualities [27] that are probably androgen-dependent [43]. In our study, however, ratings of pre-match body odour were similar for winners and losers, suggesting no prior differences in fighters’ body odour quality. Still, we obtained data on the result of only one match and have no information about the fighters' current rank position. We cannot, therefore, draw stronger conclusions about possible links between various qualities of body odour and rank in the dominance hierarchy. In other words, we do not know whether there exists any connection between dominance rank and specific odour qualities, although previous studies did find some olfactory cues to psychological dominance [31,33].

(b) Sex-related differences in rating

The absence of significant sex-linked differences in raters’ assessments in most rated characteristics suggests that these odour cues have no specific role in intra- or intersexual selection. The sole exception was masculinity ratings. Overall, losers' post-match body odour was rated as more masculine than their odour before a match. This effect was driven by male raters who evaluated losers’ body odour as more masculine after a match. Females did not perceive any difference between pre- and post-match quality. Comparison between the calculated POS values and the actual number of male raters, however, indicates a lower stability in masculinity rating by men, which is why this result should be interpreted rather cautiously. Future studies should further investigate these findings to assess their robustness.

(c) The mediating effect of affective states and hormone levels on body odour quality

If we view winning and losing a fight as a way of change in an individual's rank in dominance hierarchy, then a change of position can be reflected in body odour and others can use it to assess the result of competition. This effect could be owing to changes in hormone levels (T and/or C) associated with victory or defeat. This effect has been repeatedly shown in previous studies (e.g. [60,62]). T stimulates the proliferation of sebocytes and affects the function of apocrine sweat glands [92]. Similarly, C has an either direct or indirect link (via adrenaline) with the activity of apocrine glands [93], which can, in turn, affect the quality of body odour. Two studies that investigated the association between T and C levels and body odour quality produced rather contradictory results. Rantala et al. [72] found no significant correlation between T levels and either intensity or attractiveness of men's body odour. Interestingly, however, they found that C concentrations were positively associated with odour attractiveness, though not its intensity. Using a larger sample and a slightly different methodology (a longer sampling period and elimination of samples from men who reported violations of instructions on the use of fragranced cosmetics), Thornhill et al. [94] observed that women in the fertile phase of their menstrual cycle preferred body odours of men with higher T levels than women in the non-fertile phase. This study did not, however, find any significant relation between odour preferences and C levels.

Our study showed no significant effect of competition outcome on T levels. C levels, however, were higher after a match, which suggests that a match is a stressful event for both winners and losers. The positive relationship between C levels and perceived odour attractiveness, shown by mediation analysis, is in line with a previous study by Rantala et al. [72]. Similarly, we found that C levels did not significantly correlate with intensity ratings (a marker of the amount of perspiration), which indicates a qualitative, not quantitative effect. Glucocorticoids possess certain immunosuppressive qualities [95,96] and it has been hypothesized that only immunocompetent individuals can maintain high C levels [97], which is why such preference would be adaptive.

Another set of variables that have previously been linked to both competition outcomes and body odour are affective states. Body odour can contain cues to affective states such as happiness [98], disgust [99], fear [100], anxiety [90], stress [91], but also aggression [38] and contexts such as competition [37]. This is why we investigated possible mediating effects of changes in hormone levels and affective states. A path analysis showed not only a direct effect of competition outcome on perceived odour attractiveness, where a loss led to decrease in odour attractiveness, but also a mediating indirect effect of negative affective state, where the more negative emotions participants experienced, the less attractive was their perceived body odour. Exploratory correlation analysis showed further relationships between some odour characteristics, affective states and hormone levels, which are in line with the evidence summarized above. These findings, however, should be interpreted with caution owing to our relatively small donor sample.

(d) Study limitations

It is a common procedure in body odour studies to ask odour donors to avoid activities that could affect body odour quality, such as eating spicy food, using soaps, deodorants, demanding physical activities, smoking etc. the day before and on the day of sampling (e.g. [83,31]). Owing to logistical reasons, we were able to contact study participants only a few hours before the match. They did not, therefore, receive any such list of restrictions and followed their habitual regime without any standardization as to diet, smoking, shaving, the use of fragranced cosmetics or dietary supplements. This may have introduced some noise to the data and obscured some effects. Nevertheless, we were still able to detect some significant changes and the use of a within-subject experimental design should diminish inter-individual differences. Such an approach has a higher ecological validity, although future studies should investigate the issue under more standardized settings as well.

We explored the possible effect of injuries on body odour quality using a single question regarding participants' self-perceived pain as a proxy for suffered injuries. Admittedly, a record of actual injuries would be a more objective measure, because participants’ answers may be biased by competitiveness and excitement induced by the competition. These data were not, however, available and we did not want to overload participants with additional tasks and screenings.

In the present study, we used hedonic ratings to assess changes in body odour quality induced by winning or losing a match. Apart from explicit subjective ratings, future studies could employ some objective psychophysiological measures such as skin conductance, heart rate, possible activation of different brain areas by fMRI or variance in time activation by EEG.

Finally, future studies should collect data from the same individual both after a victory and a loss in a competition to assess the effect of outcome on body odour directly. In our field study conditions, such balanced design could not be implemented. It therefore remains as a challenge for future research.