There are consistent patterns that could be considered a non-verbal signal of guilt in humans: Guilt was most closely associated with frowning and neck touching

Are there non-verbal signals of guilt? Eglantine Julle-Danière, Jamie Whitehouse, Alexander Mielke, Aldert Vrij, Erik Gustafsson, Jérôme Micheletta, Bridget M. Waller. PLoS, April 24, 2020. https://doi.org/10.1371/journal.pone.0231756

Abstract: Guilt is a complex emotion with a potentially important social function of stimulating cooperative behaviours towards and from others, but whether the feeling of guilt is associated with a recognisable pattern of nonverbal behaviour is unknown. We examined the production and perception of guilt in two different studies, with a total of 238 participants with various places of origin. Guilt was induced experimentally, eliciting patterns of movement that were associated with both the participants’ self-reported feelings of guilt and judges’ impressions of their guilt. Guilt was most closely associated with frowning and neck touching. While there were differences between self-reported guilt and perception of guilt the findings suggest that there are consistent patterns that could be considered a non-verbal signal of guilt in humans.

Discussion

This study aimed to identify which facial movements were perceived as guilt when guilt was induced in a laboratory experiment. We found that judges gave a higher rating of guilt in videos where people were seen frowning (AU4 Brow Lowerer) and touching their neck (Neck Touching). We used instances when judges reported seeing guilt to create 1s-window of interest and conduct our analysis only on those time windows of guilt. Doing this, we identified facial movements reliably associated with the perceived expression of guilty. Judges reported other emotions at the same time as guilt in only 14% of the guilt pinpoints. Moreover, pinpoints of guilt revealed specific facial movements that were not present in control videos. This made us fairly confident that the facial expressions identified were associated with the experience (perception) of guilt.

General discussion

In two studies, we aimed to identify facial movements and behavioural displays associated with the experience of guilt in humans. In the first study, we examined the production of guilt using a novel induction technique. In the second study, we examined whether others perceived guilt from the face of those experiencing guilt. We used an extensive, bottom-up coding scheme to identify facial patterns associated with the experience (production and perception) of guilt as part of a dynamic sequence of behaviour, combined with a robust bootstrapping method to analyse our data.

We found a positive relationship between the level of self-reported guilt and the extent this individual was judged as feeling guilty by others. This supports the idea that guilt could have evolved as an observable phenomenon with a potential communicative social function. The patterns identified in this experiment showed some consistency between what people do when feeling guilty and what people see when identifying guilt. Our first study showed that guilt was associated with frowning, lip stretching and neck touching [AU4 Brow Lowerer, AU20 Lips Stretch; 59], as well as looking towards the right (AU52 Head Right, AU62 Eyes Right), which was probably an artefact of the position of the computer. Our second study showed that the identification of guilt in others was associated with frowning, eyes widening, and neck touching [AU4 Brow Lowerer, AU5 Upper Lid Raiser, AU10 Upper Lip Raiser; 59], as well as looking down and sideways (AU54 Head Down, AU61 Eyes Left, AU62 Eyes Right, AU64 Eyes Down), another potential artefact due to the experimental set-up. Thus, it seems that in this study, guilt was associated with a non-verbal pattern of frowning and neck touching.

Using a bottom-up methodology allowed us not only to approach our question without any a priori assumptions regarding the results, but it also increased the likelihood that the movements identified in our studies (AU4, AU20, and neck touch) are associated with the experience of guilt and no other secondary moral emotion. Indeed, the “guilt” pinpoints identified by the judges (Study 2) were mainly instances of identification of guilt alone, with only 14% of the total number of guilt pinpoints associated with more than one emotion (see S1 Study of Table 2). This allowed us to focus our analysis on facial movements associated with the experience of guilt only. Moreover, even though guilt is often mistaken for embarrassment or shame, the embarrassed display has been characterised by the joint production of gaze down, controlled smiles, head turns, gaze shifts, face touches [44], and the occasional blushing [90]; and the typical face of shame was described with head and gaze movements down [43–45]. None of the movements we found associated with the expression of guilt were associated with those of other negative self-conscious emotions. During the AU selection process, most facial movements associated with either embarrassment or shame were discarded from further analysis, with the only exception of face touching. Face touch can emphasise embarrassment displays, but it is not necessary for the identification of embarrassment [44]. A previous study suggested a link between blushing and admission of guilt [91]; combining FACS analysis with thermal imaging techniques might have revealed changes in facial temperature in guilty participants, which could be unconsciously used by observers in their judgments.

This bottom-up methodology also diverges from previous research examining the facial display of guilt, which is why we may have found a more concrete candidate for the display of guilt. One notable previous study used a literature-based conceptualisation of the experience of guilt to present three candidates’ displays to their participants [8]. In that study, using a top-down approach, the participants were presented with displays selected based on previous literature, which associated the experience of guilt with the experience of self-contempt, sympathy, and pain. The authors tested whether their conceptualisation of guilt accurately described a facial display associated with the experience of the emotion. The results were not conclusive as the candidates’ displays were more often associated with emotions other than guilt [8]. A more recent study associated the experience of guilty feeling with increased skin conductance and gaze avoidance [92]. We did not find gaze avoidance (i.e. actively avoiding to look in another person’s direction) to be part of the facial signal of guilt, even though participants in the guilt condition looked down and around more than participants in the control condition. Yet, this could be due to our experimental design: participants in the guilt condition might have been looking down at the laptop more than people in the control condition. It is thus unclear in our design whether guilty participants avoided eye-contact or focused on an object associated to their wrongdoing (the laptop could be incriminated for the deletion of data on the USB stick, removing the fault from them).

Both the production and perception of guilt was associated with self-directed behaviour (i.e., scratching, neck or face touching), which are often classified as displacement behaviours, and are defined as a group of behaviours that appear irrelevant to the situation in which they are displayed, but can gain communicative value over time [61]. The production of such behaviours has been shown to increase in stressful, negative, situations [93,94]. Self-directed behaviours may be used when individuals try to distance and protect themselves from an unpleasant situation, acting as a short-term diversion of attention, which could, in turn, reduce the negative feeling associated to the situation at hand [93,95,96]. Self-directed behaviour could thus help regulate the level of stress associated with emotionally challenging situations [94], such as the guilt induction experienced by our participants in Study 1. Indeed, some studies have shown that self-directed behaviours are common in situations such as embarrassment [44], discomfort [20], and anxiety and guilt [97], which focussed on hand movements and found a correlation between the production of self-directed behaviours (i.e., scratching) and anxiety and guilt feelings. In our study, we found that the experience of guilt was associated with self-directed behaviours (neck touching), which appears to be in line with previous research. However, the production of self-directed behaviours could be due to the experimental design: participants were seated at a table, in front of a computer. However, the setup is unlikely to have elicited those movements, as participants in the control condition, also seated at a computer, did not display as many self-directed behaviours.

More recent conceptualisations of emotional experiences [27,28,35–37] argue for a less universal and omnipotent link between the experience of an emotion and behavioural outcomes. In an emotional context, multiple systems will be triggered (e.g., cognitive processes, physiological systems, motor expressions; [35]), leading to multiple behavioural outcomes (e.g. facial signals), one of which might be used by observers when responding to the situation [35]. As such, an individual feeling guilty might produce multiple facial signals, one of which will be more strongly associated with the subjective, constructed, feeling of guilt (e.g., frown, lips stretch and neck touching); an observer might perceive those facial signals and rely mainly on specific ones to interpret the emotional state of the guilty individual (e.g., frown and neck touching).

It is important to remain cautious in the interpretation of our data. We need to acknowledge that if neck touching was present more in association with feelings of guilt, only 12.5%of the individuals displayed neck touching. Self-directed behaviour, however, were displayed in over 64% of the individuals during the guilt induction. Even though few participants displayed neck touching, our results showed it is a significant signal of guilt. We need to consider the possibility that by reducing our dataset to 1-second windows, we could have excluded non-verbal signals important for the onset of the experience of guilt. By focussing on the apexes of the expressions, we might have lost secondary signals contributing to the reliable identification of guilty signals. Our results provide preliminary information regarding the non-verbal signals exhibited more in association with guilty feelings. A follow-up study, using a reduced ethogram focussing on the movements identified here could allow to reach a better agreement score between coders and thus increase the K’s alpha and the validity of our results [67,68]. We also need to consider the fact that providing contextual information might have influenced the judges in their decisions. To assess the impact of context, we conducted a follow-up study comparing the judgements made with and without contextual information provided [98]. Our judgement study also presents some linguistic limitations. Even if there are differences in the appraisal and behavioural outcomes between shame and guilt, it has been previously shown that English speaker use “guilt” and “shame” interchangeably [99]. To overcome this conceptual barrier, we conducted another judgement study, without providing contextual information [98,100]. We hope to gauge how the expression of guilt is perceived when no verbal/written content needs to be understood first. Moreover, to compare various judgement methodologies [emotion words vs action tendencies vs dimensions; 101], we conducted another follow-up study to help us have a better understanding of how people conceptualise the facial expression produced when experiencing guilt, using different types of words and classification methodologies [forced choice vs free labelling vs dimensions; 100]. This way, we hoped to introduce more variability in the emotional judgements, looking at patterns of mislabelling of guilty displays.

These are the first studies to look at the genuine expression of guilt and the perception of secondary emotion using spontaneous dynamic stimuli. Judges had to rely on genuine, dynamically presented facial expressions to recognise and rate emotions. They were exploratory studies, using simple analysis and focussing on the behavioural signals associated with a guilt-inducing situation. We have however collected more extensive data; now that we identified a facial signal associated with the experience of guilt, more in-depth analysis (such as a lens modelling [35]) would be an interesting step to further break down the mechanisms associated with guilt.

Our experiments support a drive towards a new scientific culture, studying facial expressions using novel approaches removed from the dichotomous debate about nature vs nurture [73,102]. Previous research extensively looked at the behavioural consequences of guilty feelings: it can promote directed action towards those who have been wronged [4], it can reduce prejudice behaviours [13] and increase generosity [6]. We focussed on the first reactions people have when realising they did something wrong and the guilty feelings emerge; we were able to identify reliable candidates characterising the experience of self-reported guilt. Building on this, we conducted a study to investigate guilty people’s propensity to repair the relationship, as well as the impact of a facial expression on the person wronged, i.e. the victim, reaction [103]. Together, our results suggest that guilt is expressed on the face and communicates the experience of guilt to others through a signal.

Is Discrimination Widespread? Testing Assumptions About Bias on a University Campus

Campbell, Mitchell R., and Brauer G. Lab. 2020. “Is Discrimination Widespread? Testing Assumptions About Bias on a University Campus.” PsyArXiv. April 21. doi:10.31234/osf.io/evp8b

Abstract: Discrimination has persisted in our society despite steady improvements in explicit attitudes toward marginalized social groups. The most common explanation for this apparent paradox is that due to implicit biases, most individuals behave in slightly discriminatory ways outside of their own awareness (the dispersed discrimination account). Another explanation holds that a numerical minority of individuals who are moderately or highly biased are responsible for most observed discriminatory behaviors (the concentrated discrimination account). We tested these two accounts against each other in a series of studies at a large, public university (total N = 16,600). In four large-scale surveys, students from marginalized groups reported that they generally felt welcome and respected on campus (albeit less so than non-marginalized students) and that a numerical minority of their peers (around 20%) engage in subtle or explicit forms of discrimination. In five field experiments with eight different samples, we manipulated the social group membership of trained confederates and measured the behaviors of naïve bystanders. The results showed that between 5 and 20% of the participants treated the confederates belonging to marginalized groups more negatively than non-marginalized confederates. Our findings are inconsistent with the dispersed discrimination account but support the concentrated discrimination account. The Pareto principle states that, for many events, roughly 80% of the effects come from 20% of the causes. Our results suggest that the Pareto principle also applies to discrimination, at least at the large, public university where the studies were conducted. We discuss implications for pro-diversity initiatives. This paper has not been published.

During the pandemic, participants reported conforming more strongly to traditional gender roles and believing more strongly in traditional gender stereotypes than they did before

Rosenfeld, Daniel L., and A. J. Tomiyama. 2020. “Can a Pandemic Make People More Socially Conservative? Longitudinal Evidence from COVID-19.” PsyArXiv. April 22. doi:10.31234/osf.io/zg7s4

Abstract: The first months of 2020 threw people into a period of societal turmoil and pathogen threat with the novel coronavirus (COVID-19) pandemic. By promoting epistemic and existential motivational processes and activating people’s behavioral immune systems, this pandemic may have changed social and political attitudes. The current research specifically asked the following question: As COVID-19 became pronounced in the United States during March-April 2020, did people living there become more socially conservative? We present a longitudinal study (N = 695) that assessed political ideology, gender role conformity, and gender stereotypes among U.S. adults before (two months preceding) versus during the pandemic. During the pandemic, participants reported conforming more strongly to traditional gender roles and believing more strongly in traditional gender stereotypes than they did before the pandemic. Political ideology remained constant from before to during the pandemic. These findings suggest that a pandemic may promote preference for traditional gender roles.

Curiosity might correspond to an appetitive drive elicited by the state of uncertainty, because we like that state, or rather it might correspond to an aversive drive to reduce the state of uncertainty

van Lieshout, Lieke, Floris de Lange, and Roshan Cools. 2020. “Curiosity: An Appetitive or an Aversive Drive?” PsyArXiv. April 21. doi:10.31234/osf.io/s3zp4

Abstract: You probably know what kind of things you are curious about, but can you also explain what it feels like to be curious? Previous studies have demonstrated that we are particularly curious when uncertainty is high and when information provides us with a substantial update of what we know. It is unclear, however, whether this drive to seek information (curiosity) is appetitive or aversive. Curiosity might correspond to an appetitive drive elicited by the state of uncertainty, because we like that state, or rather it might correspond to an aversive drive to reduce the state of uncertainty, because we don’t like it. To investigate this, we obtained both subjective valence (happiness) and curiosity ratings from subjects who performed a lottery task that elicits uncertainty-dependent curiosity. We replicated a strong main effect of outcome uncertainty on curiosity: Curiosity increased with increasing outcome uncertainty, irrespective of whether the outcome represented a monetary gain or loss. By contrast, happiness decreased with higher outcome uncertainty. This indicates that people were more curious, but less happy about lotteries with higher outcome uncertainty. These results demonstrate that curiosity reflects an aversive drive to reduce the unpleasant state of uncertainty.

A Bayesian Multiverse Analysis of Many Labs 4: Quantifying the Evidence Against Mortality Salience

Haaf, Julia M., Suzanne Hoogeveen, Sophie Berkhout, Quentin F. Gronau, and Eric-Jan Wagenmakers. 2020. “A Bayesian Multiverse Analysis of Many Labs 4: Quantifying the Evidence Against Mortality Salience.” PsyArXiv. April 14. doi:10.31234/osf.io/cb9er

Abstract: Many Labs projects have become the gold standard for assessing the replicability of key findings in psychological science. The Many Labs 4 project recently failed to replicate the mortality salience effect where being reminded of one’s own death strengthens the own cultural identity. Here, we provide a Bayesian reanalysis of Many Labs 4 using meta-analytic and hierarchical modeling approaches and model comparison with Bayes factors. In a multiverse analysis we assess the robustness of the results with varying data inclusion criteria and prior settings. Bayesian model comparison results largely converge to a common conclusion: We find evidence against a mortality salience effect across the majority of our analyses. Even when ignoring the Bayesian model comparison results we estimate overall effect sizes so small (between d = 0.03 and d = 0.18) that it renders the entire field of mortality salience studies as uninformative.

Students are at elevated risk for mental health problems; despite increasing rates of infections & COVID-19 deaths, they had slight decreases of mental health problems & and loneliness

Fried, Eiko I. 2020. “Mental Health and Social Contact During the COVID-19 Pandemic: An Ecological Momentary Assessment Study.” PsyArXiv. April 24. doi:10.31234/osf.io/36xkp

Abstract: Students are at elevated risk for mental health problems. The COVID-19 pandemic and public health responses such as school and university closures caused once-in-a-lifetime disruptions of daily life for most students. In March 2020, during the beginning of the outbreak in the Netherlands, we used Ecological Momentary Assessment to follow 80 bachelor students 4 times a day for 2 weeks. Despite rapidly increasing rates of infections and deaths, short-term dynamics revealed slight decreases of mental health problems, COVID-19 related concerns, and loneliness, especially in the first few days of the study. Students showed no changes in the frequency of in-person social activities. Dynamic network models indicated that social activities were negatively related to being at home, and identified reinforcing vicious cycles among mental health problems and being alone, which in turn predicted concerns about COVID-19. Findings and implications are discussed in detail.

The Psychology of Queuing

Furnham, A. , Treglown, L. and Horne, G. (2020) The Psychology of Queuing. Psychology, 11, 480-498. doi: 10.4236/psych.2020.113033.

ABSTRACT: Queuing is still a fundamental function of how many businesses operate, yet there is not a clear understanding to impact the queuing environment to increase the amount of time an individual is willing to wait, improving an individual’s queuing experience, as well as reduce frustration and reneging. This paper presents a synthesis of the academic literature on queuing phenomenon. In particular, the paper focuses on the social norms of queuing, how they are upheld, and reactions to when they are violated; and environmental moderators, examining the impact of factors such as queue length, presence of information, music, light, and scent. Issues like the effect of number of people in a queue, personal space and the ideal queuing environment are discussed. Finally, this paper addresses limitations within the current body of research as well as proposing an agenda for future research.

KEYWORDS: Queuing, Waiting, Time, Environmental Moderators, Social Norms, Personal Space, Ideal Queues

9.6. Employee Visibility

The patience of queuers has also been known to fluctuate depending on the visibility of employees. In particular, whether the queuers perceive the employees to be working hard to serve all those who are queuing. Studies have shown that customer satisfaction in banks is strongly predicted by whether queuers believed all tellers to be doing their best to serve all customers (Clemmer & Schneider, 1989) . Furthermore, queuers become more frustrated when service providers are not working hard (e.g. talking with their co-workers) as this information is used to predict a longer wait (Larson, 1987) .

‘They can’t fool me, but they can fool the others!’ Third person effect and fake news detection.

‘They can’t fool me, but they can fool the others!’ Third person effect and fake news detection. Nicoleta Corbu et al. European Journal of Communication, February 17, 2020. https://doi.org/10.1177/0267323120903686

Abstract: The aftermath of the 2016 US Presidential Elections and the Brexit campaign in Europe have opened the floor to heated debates about fake news and the dangers that these phenomena pose to elections and to democracy, in general. Despite a growing body of scholarly literature on fake news and its close relatives misinformation, disinformation or, more encompassing, communication and information disorders, few studies have so far attempted to empirically account for the effects that fake news might have, especially with respect to what communication scholars call the third person effect. This study aims to provide empirical evidence for the third person effect in the case of people’s self-perceived ability to detect fake news and of their perception of others’ ability to detect it. Based on a survey run in August 2018 and comprising a national, diverse sample of Romanian adults (N = 813), this research reveals that there is a significant third person effect regarding people’s self-reported ability to spot fake news and that this effect is stronger when people compare their fake news detection literacy to that of distant others than to that close others. Furthermore, this study shows that the most important predictors of third person effect related to fake news detection are education, income, interest in politics, Facebook dependency and confirmation bias, with age being a non-significant predictor.

Keywords: Distant and close others, fake news, predictors, third person effect

“Wonderful but Weak”: Children’s Ambivalent Attitudes Toward Women

“Wonderful but Weak”: Children’s Ambivalent Attitudes Toward Women. Matthew D. Hammond & Andrei Cimpian. Sex Roles, Apr 23 2020. https://rd.springer.com/article/10.1007/s11199-020-01150-0

Abstract: According to ambivalent sexism theory, prejudice toward women has two forms: hostile (i.e., antipathy toward women) and benevolent (i.e., patronizing and paternalistic attitudes toward women). We investigated whether 5- to 11-year-old children’s gender attitudes exhibit this bipartite, ambivalent structure. Consistent with this possibility, latent variable modeling on a new developmentally appropriate instrument revealed that children’s (n = 237) hostile and benevolent attitudes were two distinct but positively associated factors. Using this instrument, we then explored age and U.S. regional differences in ambivalent gender attitudes, as well as whether these attitudes predicted self-evaluations and preferences associated with traditional gender roles. Stronger agreement with hostile and benevolent gender attitudes was found among younger children, except for boys’ benevolent attitudes, which did not vary with age. Children also reported lower agreement with benevolent gender attitudes in a more gender-egalitarian region of the United States (New York vs. Illinois). Finally, children’s benevolent and hostile attitudes differentially predicted their self-evaluations (e.g., boys’ benevolent vs. hostile attitudes predicted higher vs. lower self-evaluations of warmth, respectively). No evidence emerged for links between gender attitudes and traditional career or relationship expectations. These findings provide the first known evidence that children’s gender attitudes are ambivalent—comprising distinct, but positively related, dimensions of subjective positivity and negativity.

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

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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