Talking to Cows: Reactions to Different Auditory Stimuli During Gentle Human-Animal Interactions

Talking to Cows: Reactions to Different Auditory Stimuli During Gentle Human-Animal Interactions. Annika Lange et al. Front. Psychol., October 15 2020. https://doi.org/10.3389/fpsyg.2020.579346

Abstract: The quality of the animal-human relationship and, consequently, the welfare of animals can be improved by gentle interactions such as stroking and talking. The perception of different stimuli during these interactions likely plays a key role in their emotional experience, but studies are scarce. During experiments, the standardization of verbal stimuli could be increased by using a recording. However, the use of a playback might influence the perception differently than “live” talking, which is closer to on-farm practice. Thus, we compared heifers' (n = 28) reactions to stroking while an experimenter was talking soothingly (“live”) or while a recording of the experimenter talking soothingly was played (“playback”). Each animal was tested three times per condition and each trial comprised three phases: pre-stimulus, stimulus (stroking and talking) and post-stimulus. In both conditions, similar phrases with positive content were spoken calmly, using long low-pitched vowels. All tests were video recorded and analyzed for behaviors associated with different affective states. Effects on the heifers' cardiac parameters were assessed using analysis of heart rate variability. Independently of the auditory stimuli, longer durations of neck stretching occurred during stroking, supporting our hypothesis of a positive perception of stroking. Observation of ear positions revealed longer durations of the “back up” position and less ear flicking and changes of ear positions during stroking. The predicted decrease in HR during stroking was not confirmed; instead we found a slightly increased mean HR during stroking with a subsequent decrease in HR, which was stronger after stroking with live talking. In combination with differences in HRV parameters, our findings suggest that live talking might have been more pleasurable to the animals and had a stronger relaxing effect than “playback.” The results regarding the effects of the degree of standardization of the stimulus on the variability of the data were inconclusive. We thus conclude that the use of recorded auditory stimuli to promote positive affective states during human-animal interactions in experimental settings is possible, but not necessarily preferable.

Discussion

We compared the reactions of heifers to stroking while applying two different auditory stimuli: the stroker talking directly to the animals in a gentle voice or a recording of the stroker's talking. We found behavioral and physiological indications of a positive perception of the interactions for both auditory stimuli. While the behavioral reactions to gentle interactions did not differ statistically, some of the cardiac parameters indicated differences between the auditory stimuli, also shortly after the presentation of the stimulus had ended.

Perception of Each Treatment

Both treatments led to changes in behavior during the STIM phase that indicate a positive perception: During stroking, the heifers showed significantly longer durations of neck stretching, a behavior shown during intraspecific social grooming (Sambraus, 1969; Reinhardt et al., 1986; Schmied et al., 2005), which is often actively solicited, and stroking by humans (Waiblinger et al., 2004; Schmied et al., 2008; Lürzel et al., 2015a). It is interpreted a sign of enjoyment, and it can thus be assumed that the situation is perceived as positive.

In a previous, similar experiment (Lange et al., 2020), we observed decreases of ear flicking and changes of ear position during stroking with no auditory stimuli. The present study confirms this pattern. The animals showed less ear flicking during STIM than PRE, a behavior mostly associated with negative affective states, such as pain after dehorning (Heinrich et al., 2010; Neave et al., 2013) or reactions to insect attacks (Mooring et al., 2007).

During STIM, the animals also changed the positions of their ears less often than in PRE. Frequencies of changes of ear positions were lower in sheep feeding (Reefmann et al., 2009a) or voluntarily being groomed by a human (Reefmann et al., 2009b) than during separation from the herd. In contrast, dairy cows showed an increased frequency of changes of ear positions during stroking compared to before or after (Proctor and Carder, 2014), which might however have been caused by small differences in experimental design, such as the stroker approaching at the beginning of the stroking phase. In contrast, the decrease in changes of ear positions and ear flicking during stroking in the current as well as in our previous study (Lange et al., 2020) indicates an association of a reduction of these behaviors with a positive, low-arousal state also in cattle.

However, for some of the behaviors we expected to indicate affective states, the treatment did not lead to significant differences: previously observed effects of stroking (Lange et al., 2020) on the duration of the animal resting its head and the time spent in contact with the experimenter were not confirmed in this study. These findings might be connected with the auditory stimulus, which might keep the animal comparatively more attentive to a certain degree and thus limit the intensity of the relaxation.

In an attempt to reflect the continuous nature of ear positions, we recorded nine different positions along the vertical and the horizontal axis: back up, back center, back down, center up, center, center down, forward up, forward center and forward down, plus ear hanging. During stroking, durations of the back up position increased significantly, while durations of forward up and ear low decreased, mostly in line with our previous experiment (Lange et al., 2020). The tendency toward decreased durations of forward up might indicate lowered vigilance (Boissy and Dumont, 2002), which is associated with less fear (Welp et al., 2004), and could corroborate the hypothesis that stroking induces positive low-arousal states.

We predicted to find longer durations of ear low during stroking, because low ear positions, including ear hanging, were associated with low-arousal, positive affective states in dairy cows in previous studies (Schmied et al., 2008; Proctor and Carder, 2014). However, we observed predominantly back up positions and surprisingly rare occurrences of ear low. One possible reason might have been the strokers' position kneeling next to the lying animal and resulting in the auditory signal being located above and behind the heifers' ears in both conditions. Since the ear position pattern was very similar to the one found in our previous study without vocal stimulation (Lange et al., 2020), however, the effect of the auditory stimulus seems not to have had a strong influence on ear positions, possibly because cattle have a relatively low sound-localization acuity compared with other mammals (Heffner and Heffner, 1992); the stroker's position relative to the animal's head may nevertheless be relevant.

Furthermore, the effects that we saw in STIM were not observed in POST, contrary to our hypothesis of longer-lasting effects of the treatment on behavior. However, some of the observed behaviors (such as neck stretching and the different ear positions) are more immediate reactions to positive stimuli and do not allow to observe longer-lasting changes in affective states.

Comparison of the Treatments

As there were no significant differences in the behavioral reactions to the two different auditory stimuli, stroking and talking in a gentle voice per se seem to have a stronger effect on the behavior than the source of the auditory stimulus. As this experiment did not include a treatment where the animals were stroked without any auditory stimulation, we cannot infer any information on whether gentle talking in general enhances or diminishes the positive effects of stroking, but the results are very similar to our previous study, where the animals were stroked without acoustic stimulation. Stroking can elicit quite strong effects on physiology and behavior in different species (rats: Holst et al., 2005; cows: Schmied et al., 2010; cats: Gourkow et al., 2014; lambs: Coulon et al., 2015; horses: Lansade et al., 2018), which might exceed possible consequences of small differences in auditory stimuli. Regarding the absence of significant differences in behavior, it seems plausible that the heifers did not discern the two auditory stimuli, at least not to an extent where it would have affected their behavior. Furthermore, the mismatch of experimenter and playback voice did not have a significant effect on any of the behaviors. Indeed, there is a substantial amount of literature in different species indicating that they do not necessarily distinguish playback from live auditory stimuli: playback is used successfully in studies investigating bird behavior (Douglas and Mennill, 2010), dogs react to dog-directed human speech played back from a loudspeaker (Ben-Aderet et al., 2017; Benjamin and Slocombe, 2018), and dairy cows increase their production when exposed to a playback of calf vocalizations (Pollock and Hurnik, 1978; McCowan et al., 2002; no effect if calves are reared with their mothers: Zipp et al., 2013). Other characteristics of speech might thus have a stronger impact on the animals' behavior than the characteristics induced by the type of source.

On the other hand, the analysis of cardiac parameters points toward a different perception of the two auditory stimuli. In both conditions, HR increased from PRE to STIM and decreased from STIM to POST, but this decrease was significantly more pronounced in the “live” condition, indicating a stronger relaxation effect of live talking after the presentation of the stimulus. The slight increase of HR during STIM in both conditions seems to contradict our expectation that our treatment would induce a low-arousal state. However, it is in line with previous findings reporting an increased HR of lying animals that were licked by conspecifics (Laister et al., 2011) or receiving a stroking treatment (Lange et al., 2020) and might be caused by physical reactions to stroking (e.g., neck stretching) more than by a meaningful change in arousal or affective state (Lange et al., 2020).

Independently of the changes in HR, there were some significant effects of the conditions on HRV parameters: HF increased in POST in the “live” condition, but decreased in POST in the “playback” condition. It is widely accepted that HF increases with increasing activity of the parasympathetic branch of the autonomic nervous system (Task Force of ESP and NASPE, 1996; von Borell et al., 2007). The increased values suggest a higher parasympathetic activity after stroking in the “live,” but not the “playback” condition. An increased HF may be associated with positive emotions (McCraty et al., 1995; von Borell et al., 2007) and was found in horses regularly receiving a relaxing massage (Kowalik et al., 2017). This increase in HF was not accompanied by an increase in RMSSD, although both represent vagal activity and are often correlated (Task Force of ESP and NASPE, 1996; Hagen et al., 2005; von Borell et al., 2007; Shaffer et al., 2014). However, changes in RMSSD were not consistently observed in other studies investigating different affective states in animals (Reefmann et al., 2012; Travain et al., 2016). RMSSD might therefore be a suboptimal indicator of animal affective states (Gygax et al., 2013; Tamioso et al., 2018). A different pattern emerged for SDNN: values increased from PRE to STIM in the “live” condition, and decreased again in POST, whereas in the “playback” condition, SDNN reached its highest values in POST. SDNN reflects influences of both parasympathetic and sympathetic activity (von Borell et al., 2007; Shaffer et al., 2014). Together with the decrease of RMSSD/SDNN during live talking, these findings might indicate that the “live” condition led to higher sympathetic activity during stroking and talking, possibly indicating positive arousal in response to being stroked (Tamioso et al., 2018). The increase of RMSSD/SDNN in “live” in POST is in line with increased values observed in sheep being brushed by a familiar human (Tamioso et al., 2018), and, in combination with the observed increase of HF in POST in “live,” indicates a shift toward vagal dominance after live talking. These patterns were not observed in the “playback” condition; contrarily, SDNN increased in POST, while RMSSD/SDNN and HF decreased slightly, possibly indicating a relative shift towards sympathetic regulation after stroking with “playback” stimulation.

In combination, the HRV results suggest that live talking may have been more pleasurable to the animals than “playback” and led to increased parasympathetic activity in the POST phase. They thus support the interpretation of a more pronounced relaxation effect indicated by the stronger decrease of HR in POST in “live” than in “playback.” The difference between the two auditory stimuli might be caused by losses of lower and higher frequencies of recorded sound, which have been found to cause a decline in dog's responses to commands, especially in the absence of certain non-verbal cues (Fukuzawa et al., 2005). As we could not measure the actual sound pressure reaching the animals' ears directly, we can neither exclude the possibility that there might have been other systematic differences between the acoustic signals produced by two sources, such as consistent differences in volume, which might have contributed to eliciting higher or lower arousal. Another difference between the situations might have been produced by a subconscious change of the stroker's body language or attention toward the animal during live talking. However, stroker behavior was standardized as far as possible – in both conditions, the stroker was calmly sitting next to the heifer's shoulder, focused on stroking the animal. Great care was taken to match the “playback” condition not only in body posture and calm breathing, but also in mental focus and intention of interacting gently with the animal, trying to minimize possible differences in non-verbal communication.

We hypothesized that the higher degree of standardization in the “playback” stimulus would lead to decreased variability in the data. However, the variability of the responses as indicated by the precision parameters revealed a conflicting pattern, indicating that the relationship between the degree of standardization of the treatment and the variability in the observed behavior is more complex than expected or has different effects on different parameters. The higher degree of standardization in “playback” stimuli did not lead to a generally reduced variability and therefore should not be the main criterion for preference of playback stimuli for gentle human-animal interactions in experimental settings.

Quotation errors in high-impact general science journals: Found a total error rate of 25%, which tracks well with error rates found in similar studies in other academic fields

Quotation errors in general science journals. Neal Smith and Aaron Cumberledge. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, October 14 2020. https://doi.org/10.1098/rspa.2020.0538

Abstract: Due to the incremental nature of scientific discovery, scientific writing requires extensive referencing to the writings of others. The accuracy of this referencing is vital, yet errors do occur. These errors are called ‘quotation errors’. This paper presents the first assessment of quotation errors in high-impact general science journals. A total of 250 random citations were examined. The propositions being cited were compared with the referenced materials to verify whether the propositions could be substantiated by those materials. The study found a total error rate of 25%. This result tracks well with error rates found in similar studies in other academic fields. Additionally, several suggestions are offered that may help to decrease these errors and make similar studies more feasible in the future.

4. Discussion

This study is the first review of quotation errors in high-impact general science journals. Errors were found to exist in considerable numbers. This demonstrates a weakness in the current use of references in scientific writing. There may be several reasons for these errors. Stochastic modelling suggests that 70–90% of references are copied second-hand from other articles' reference lists [26]. In addition, it has been argued through analysis of misprints that only about 20% of authors citing a paper have actually read the original [27]. As suggested by other quotation error researchers, authors could avoid errors through greater diligence [1,4–5,9]. There is also a lack of agreement regarding the correct reasons to include citations in scientific papers [28]. This could contribute to the citing of inappropriate references. Finally, quotation errors may occur though deliberate malpractice with the goal of increasing the citation metrics for the cited references [4].

Regardless of the cause, the most pragmatic approach to improving this problem is to improve the review and verification of references [1,20]. In the current state of academic literature, this is a very time-consuming task. In this study, it took two reviewers months of work to examine only 250 citations. The 500 articles from which we randomly selected our sample had a total of 26 344 references (many of which were cited multiple times). This suggests that it is unfeasible for editors or reviewers to thoroughly check all citations for substantiation. Therefore, we present two suggestions that would make systematic checking of references far more feasible.

First, most importantly, journals should change their citation styles to require page numbers. None of the high-impact journals reviewed require or even allow the inclusion of page numbers with in-text citations. In the verification process, a huge amount of time is spent searching through references to find the information being cited. Some books and reports are hundreds or thousands of pages long. Furthermore, even relatively short journal articles of 8–10 pages can be very dense and take a long time to thoroughly examine. Requiring page numbers (or paragraph numbers, etc.) places a slightly higher burden on the authors in exchange for significantly lightening the workload of potential reviewers. Lengthy references are often used to cite one specific piece of information, and it is not reasonable to expect reviewers to search through them to find that information. Page numbers should be required. One possible exception to this rule could be when referring to a study as a whole. However, even in those cases, propositions can nearly always be substantiated by referring to the page number of the introduction or abstract of a paper. This makes quotation errors easier to check for, increasing the likelihood of detection both before and after publication.

Requiring page numbers with in-text citations would constitute a significant change for academic publishers. The five journals in our study all use numbered endnotes, with a single endnote used for each reference regardless of how many times it is cited. To require page numbers in the text, these journals would have to either require page numbers to be included in each in-text citation (along with an endnote reference number), require separate endnotes containing page numbers for each citation of the reference, or abandon endnote citation altogether for some style of parenthetical citation. However, the continued prevalence of quotation errors is a significant problem that more than justifies the one-time cost of journals adopting new in-text citation policies.

We are not necessarily suggesting that systematic review of all quotations should be done by reviewers/editorial staff. However, systematic review of quotations would have benefits. There is a reason that the academic review process exists: to verify and improve the quality of scientific literature. Minimizing quotation errors is certainly one way to do that, and reference verification by journal staff has been significantly correlated with fewer quotation errors [10]. However, even in the absence of such a system of editorial review, including page numbers would give readers and reviewers in studies such as ours a better chance at successfully detecting quotation errors when they happen. Furthermore, the simple act of requiring authors to specifically locate and cite a specific page would necessitate them taking more care with their use of citations.

Our second suggestion refers specifically to the Impossible to Substantiate category. We are not aware of any previous studies that include an Impossible to Substantiate category, so further explanation and justification for its inclusion is in order. Essentially, this category refers to statements being cited that either lack a clear proposition or contain a proposition that cannot be substantiated through an outside reference. For example, an article might merely mention a novel material and cite a reference discussing that material. There is no specific proposition being made. The reference is simply giving additional background information. Therefore, substantiation is impossible. In other cases, statements cannot possibly be substantiated with a reference. For example, it was not uncommon in the articles surveyed for the methods section to be replaced (in whole or in part) with a citation. Here, there is a claim: ‘The methods from this reference were used’. However, it is not possible to substantiate this claim, because the article does not include the details of the methods used for comparison.

Some may consider this approach to be overly fastidious. However, there is no good reason to allow this type of inexact and non-verifiable referencing to pervade scientific literature. The most likely reason for this type of citing is to shorten articles to save printing space. This is a weak justification in the digital age. If background information is so unimportant that it does not merit a few words in the text (‘discussed in reference 15’ or ‘see reference 15 for the history of material X’ for example), then instead of using a propositionless citation, the information should be edited out of the paper proper and included as a supplement. The citing of methods sections and other unsubstantiatable claims could be dealt with in the same manner.

Of the previous quotation error studies reviewed, 71% did not mention string citations at all, and 14% specifically excluded string citations from their research [2–5,7–23]. Only one study specifically noted a difference in error rate between single and string citations. Surprisingly, that study came to a directly opposite conclusion regarding string citations, finding major errors more common in string citations [9]. The reason behind this discrepancy is unclear, although it may be related to the study's enormous sample size (more than six times larger than the other studies reviewed) or its very limited topic focus (peer-reviewed orthopedic literature related to the scaphoid). It is also not methodologically clear if the study required each reference in a string citation to substantiate the entire proposition being made. Our study did not require this. It required only that all the references in the string—as a whole—substantiate the entire proposition and for the reference being checked to contribute to that substantiation. References mentioned in string citations tend to make overlapping points and are often redundant [29]. Therefore, using our methodology, it seems reasonable to expect string citations to be more likely to be Fully Substantiated, not less. Still, the connection between string citations and substantiation needs further investigation.

Previous research has found quotation errors in the physical, life and social sciences [1–23]. This study extends that research to a cross section of high-impact general science journals, finding a similar rate of errors. However, further research is needed to more fully understand the problem. This paper reviewed only a total of 250 citations, which is less than 1% of the citations included in the five target journals over the course of a year. Although this sample is in keeping with the sample size of similar studies [2–5,7–8,10–23], a larger sample could produce more meaningful results. The main barrier to using a larger sample is the time cost involved. By improving citation and referencing standards for journal articles, reviewers should be able to check references more quickly. Furthermore, in this study the reviewers were not experts in the scientific disciplines to which the references belonged. Even though only two references (0.08%) were deemed too difficult to understand, some classifications required extensive research on the part of the reviewers. Expert reviewers should be able to work at a significantly faster pace, allowing for larger sample sizes. Further review of references can better show the extent of quotation errors in scientific literature. A better understanding of these errors can help decrease them, leading to better, more rigorously supported science.

Script Effects as the Hidden Drive of the Mind, Cognition, and Culture

Script Effects as the Hidden Drive of the Mind, Cognition, and Culture. Hye K. Pae. Literacy Studies book series (LITS, volume 21). Springer, Cham. Oct 2020. https://link.springer.com/book/10.1007/978-3-030-55152-0

Introduction: This open access volume reveals the hidden power of the script we read in and how it shapes and drives our minds, ways of thinking, and cultures.  Expanding on the Linguistic Relativity Hypothesis (i.e., the idea that language affects the way we think), this volume proposes the “Script Relativity Hypothesis” (i.e., the idea that the script in which we read affects the way we think) by offering a unique perspective on the effect of script (alphabets, morphosyllabaries, or multi-scripts) on our attention, perception, and problem-solving.  Once we become literate, fundamental changes occur in our brain circuitry to accommodate the new demand for resources.  The powerful effects of literacy have been demonstrated by research on literate versus illiterate individuals, as well as cross-scriptal transfer, indicating that literate brain networks function differently, depending on the script being read.  This book identifies the locus of differences between the Chinese, Japanese, and Koreans, and between the East and the West, as the neural underpinnings of literacy.  To support the “Script Relativity Hypothesis”, it reviews a vast corpus of empirical studies, including anthropological accounts of human civilization, social psychology, cognitive psychology, neuropsychology, applied linguistics, second language studies, and cross-cultural communication. It also discusses the impact of reading from screens in the digital age, as well as the impact of bi-script or multi-script use, which is a growing trend around the globe.  As a result, our minds, ways of thinking, and cultures are now growing closer together, not farther apart.

Keywords: Open AccessThe emergence of written languageLinguistic relativity and readingPsychological mechanisms of readingScript effects and critical contrastive rhetoricWriting systems and literacy

Women’s short-term mating orientation was associated with attraction to men with greater chests; women who perceived themselves as attractive rated them as more attractive

Effects of Women’s Short-Term Mating Orientation and Self-Perceived Attractiveness in Rating and Viewing Men’s Waist to Chest Ratios. Ray Garza & Jennifer Byrd-Craven. Archives of Sexual Behavior, Oct 14 2020. https://link.springer.com/article/10.1007/s10508-020-01846-0

Rolf Degen's take: https://twitter.com/DegenRolf/status/1316608849680498689

Abstract: Women’s mating strategies are dependent on multiple factors, such as identifying which men advertise physical features indicating high genetic quality, as well as identifying which men are willing to invest in offspring. Research has suggested that women pursuing short-term mating prioritize physical attraction to facilitate the acquisition of good genes. Although it is known that physical characteristics are important in mate choice, research investigating the saliency of physical features in assessing male fitness has not been readily explored. The current study used an eye-tracking paradigm to investigate the role of short-term mating in women and their attraction and visual attention to men’s waist to chest ratios (WCRs). Women’s short-term mating orientation (N = 130) was associated with attraction to men with low WCRs; however, their visual attention was not influenced by their mating strategy. Interestingly, women who perceived themselves as attractive rated men with low WCRs as more attractive and allocated attentional resources to physical features important in mate choice, such as the head and midriff region. The findings from this study lend some support to sexual strategies theory (Buss & Schmitt, 1993) and strategic pluralism (Gangestad & Simpson, 2000), and they suggest that mate preferences may be calibrated as a function of one’s mate value.

Discussion

This study examined how short-term mating orientation in women influenced their ratings and visual attention to men’s WCRs. Short-term mating oriented women rated men with low WCRs (0.7) as more attractive, supporting the first hypothesis. Since the costs of low investment may be less concerning for women pursing a short-term mating strategy, they may demonstrate a stronger preference for features associated with masculinity (Little et al., 2011). Women perceive men with low WCRs to be dominant (Hughes & Gallup, 2002), masculine (Provost et al., 2006, 2008) and immunocompetent (Dixson et al., of attraction (Fan et al., 2005; Garza et al., 2017; Garza & ByrdCraven, 2019; Maisey et al., 1999; Swami & Tovee, 2005). In pursuing a short-term mating strategy, women have more to gain from securing genes from men who display increased fitness, and they may have more to lose from securing masculine men if pursuing a long-term mating strategy, as a competitive man’s effort can be focused on mating and not parenting (Buss & Schmitt, 1993). Self-perceived attractiveness was a stronger predictor in ratings for attractiveness than was short-term mating orientation. Women who perceived themselves as more attractive rated men with low WCRs (0.7) as more attractive compared with women who rated themselves as less attractive. Women who consider themselves to be more attractive may be more competitive and are better able to attain high-quality mates as it relates to their own mate value (Buss & Shackelford, 2008). This suggests that mate preferences may be calibrated as a function of one’s mate own value (Buss & Schmitt, 1993), where highly attractive women prefer men with physical traits similar to their own attractiveness, consistent with assortative mating. Although women’s short-term mating orientation was associated with attractiveness ratings to men with low (0.7) WCRs, behavioral data in the form of eye movements did not show a similar trend. Regardless of mating strategies, women’s eye movements were centered on medium WCR (0.8) men, and they focused their visual attention to the head and midriff region, supporting previous research on eye movements and attentional biases to men’s bodies (Dixson et al., 2014; Garza et al., 2017; Garza & Byrd-Craven, 2019). Women’s focus on the face at the earliest stages of processing (i.e., first fixation duration) indicates a reliance on physical communicative cues (e.g., facial features) and then focuses on features associated with immunocompetence and health (e.g., midriff region). Given the association between self-perceived attractiveness and preferences for men with low WCRs (0.7), self-perceived attractiveness was also investigated in predicting eye movements. Women who perceived themselves as more attractive spent less time viewing the chest region at the early stages of visual processing (i.e., first fixation duration) and viewed the midriff longer. Findings for first fixation duration may be interpreted in two ways: (1) high mate value women may not need to rely on specific features (e.g., chest region) at first glance when viewing men because they already know what they are looking for overall, independent of ROI, or (2) similar to Little et al. (2011), women who perceived themselves to be less attractive show more of an exaggeration in preferences associated with masculinity (i.e., chest features). For gaze duration, high mate value women show an interest to the midriff region, as the midriff regions is a physical cue that can be used to infer health status (i.e., body fat displays), and high mate value women are searching for men that demonstrate high-quality status. These findings contribute to research demonstrating the importance of mating strategies and mate value in physical attractiveness to men. Previous research has demonstrated the role of short-term mating in self-reported ratings of attractiveness to men with different somatotypes (Provost et al., 2006), masculinity (Little et al., 2011; Provost et al., 2008), facial masculinity (Little et al., 2002, 2011; Perrett et al., 1998), and waist to chest ratios (Garza & Byrd-Craven, 2019). Moreover, they suggest that mating strategies function differently in mate choice irrespective of how a potential mate is being processed visually. That is, when considering one’s own sociosexual attitudes, women’s visual assessments of men may not differ compared to their overall ratings of attractiveness. This has been demonstrated before by Dixson et al. (2014), where no significant differences were apparent in processing men with different somatotypes for short or long-term mating contexts. More importantly, the findings demonstrate the role of mate value, as women high on self-perceived attractiveness found men with low WCRs more attractive and showed attentional biases to specific regions of men’s bodies. Research by Buss and Shackelford (2008) has shown that women high on selfperceived attractiveness prefer men who are more masculinized and physically fit. Similar accounts have been shown by Little et al. (2011), where attractive women preferred slightly masculine facial features in men. Women may also be looking for mates that display equivalent levels of traits, as mate value has shown to guide how individuals choose and design a potential mate (Edlund & Sagarin, 2010). Additionally, women who perceived themselves as more attractive might be better able to guard against mate poaching. Women high in mate value have been shown to be more controlling of their partner’s behaviors (Danel et al., 2017), by limiting the cost associated with partner desertion. The discrepancy between short-term mating and eye movements could reflect the importance of saliency in an eye-tracking task. That is, participants simply completed a self-reported measurement of short-term mating and were not subjected to an experimental manipulation where mating was made salient. Possibly, if mating context is made salient, there are specific cognitive mechanisms that are activated in the pursuit of choosing and evaluating a potential mate. Mating motives have shown to activate perceptions, cognitions, and behaviors that are used in mate search and reproductive behavior (Griskevicius, Goldstein, Mortensen, Cialdini, & Kenrick, 2006; Maner et al., 2005). Nonetheless, future research on mate preferences should incorporate the use of behavioral data, in addition to self-report measures of attraction. The use of behavioral measures, such as eye tracking, provides insight into early and late onset ratings rather than reliance on outputs of a decision that is effortful and subject to experimenter expectancy (Conklin et al., 2018; Krupp, 2008).

Rolf Degen summarizing... People have mixed feeling about conformists, looking down on those who bow to the majority to gain approval, approving of those who do it out of solidarity, and they judge their own conformity more favorably than others'

Benevolent Conformity: The Influence of Perceived Motives on Judgments of Conformity. Matthew Wice, Shai Davidai. Personality and Social Psychology Bulletin, October 14, 2020. https://doi.org/10.1177/0146167220963702

Rolf Degen's take: https://twitter.com/DegenRolf/status/1316440685755748357

Abstract: Although people often disapprove of conformity, they also dislike when others deviate from group norms. What explains this ambivalence? We hypothesized that judgments of conformity would be affected by whether people view it as motivated by self-interested or benevolent motives. Four studies (N = 808), using both hypothetical and real-life instances of conformity, support this prediction. We find that people judge those who conform to gain social approval (self-interested conformity) as weak-willed, but those who conform out of concern for their group (benevolent conformity) as competent and possessing strong character. In addition, we predict and find that people view self-interested conformity as “fake” but benevolent conformity as revealing one’s true self. Finally, we show that differences in perceived intentions explain how people sustain positive self-regard while succumbing to group pressures and why people judge their own conformity more favorably than others’ conformity. We discuss implications for encouraging and discouraging conformity.

Keywords: conformity, social judgment, attributions, self–other difference, authenticity

In two different cultures and religious traditions, blocking opioid receptors inhibits social bonding in rituals

Blocking mu-opioid receptors inhibits social bonding in rituals. S. J. Charles, M. Farias, V. van Mulukom, A. Saraswati, S. Dein, F. Watts and R. I. M. Dunbar. , October 14 2020. https://doi.org/10.1098/rsbl.2020.0485

Rolf Degen's take: https://twitter.com/DegenRolf/status/1316377518480535552

Abstract: Religious rituals are universal human practices that play a seminal role in community bonding. In two experiments, we tested the role of mu-opioids as the active factor fostering social bonding. We used a mu-opioid blocker (naltrexone) in two double-blind studies of rituals from different religious traditions. We found the same effect across both studies, with naltrexone leading to significantly lower social bonding compared with placebo. These studies suggest that mu-opioids play a significant role in experiences of social bonding within ritual contexts.

4. General discussion

Previous work on the role of opioids on social bonding has been conducted either via proxy measures [18,40,41] or via daily self-reporting of social bonding after it has taken place [24]. Here, we sought to understand the role of opioids on social bonding in an ecologically valid setting [2,18,42]. We have demonstrated that mu-opioids play a key role in the social bonding experience during ritual by showing that naltrexone, compared with placebo, lowers feelings of bonding. These results were consistent and individually significant across the two studies. This is the first set of studies to demonstrate the causal role of mu-opioids on bonding during a ritual, and we do so in both a laboratory and a field setting.

It has often been suggested that one of the primary functions of religion is to promote social bonding and thus enhance group solidarity (e.g. [43]). These results extend previous work by providing evidence for a mechanism for how group solidarity might be promoted. In so doing, the results support the brain-opioid theory of social attachment [2,44], which argues that the endogenous opioid system is a major neuroendocrine system underlying social bonding.

Although the sample size of study 1 is small, it adds significantly to study 2 by showing that the results hold across two different cultures and ritual types, thereby providing strong ecological validity [39]. Although it is possible that other neurochemicals such as oxytocin [45,46] and dopamine [47] might also play a role in the social bonding experience, studies of the receptor genetics for these other neurochemicals suggest that these play a more specialized and much less prominent role compared with β-endorphins [1,4]. Still, future research could seek to rule out the role of other such neurochemicals that have been proposed to play a role in bonding in further double-blind studies to determine which neurochemicals are necessary and/or sufficient for social bonding to occur. Study 1 (but not study 2) suffered from the limitation that it recruited very few males, and it would be desirable to increase the gender representation in future studies. It should also be noted that naltrexone may also block the kappa-opioid receptors [20,21], which have a particular affinity with dynorphins. Although this makes it difficult to be absolutely certain that the primary target is the mu-receptors, primate social bonding has been explicitly identified in previous studies with the β-endorphins [48], which have a particular affinity for the mu-receptors.

In summary, we provide the first placebo-controlled, double-blind studies to examine the pharmacological basis for the role of religious rituals in social bonding. These studies provide a prima facie case on the neurochemical mechanisms underlying ritual social bonding.

Key examples of exaggerated claims & embellishing words from host–parasite systems found in the scientific literature appear to show that some of the fiction surrounding host manipulation has since become fact

When fiction becomes fact: exaggerating host manipulation by parasites. Jean-François Doherty. Proceedings of the Royal Society B: Biological Sciences, Volume 287, Issue 1936, October 14 2020. https://doi.org/10.1098/rspb.2020.1081

Rolf Degen's take: 

Abstract: In an era where some find fake news around every corner, the use of sensationalism has inevitably found its way into the scientific literature. This is especially the case for host manipulation by parasites, a phenomenon in which a parasite causes remarkable change in the appearance or behaviour of its host. This concept, which has deservedly garnered popular interest throughout the world in recent years, is nearly 50 years old. In the past two decades, the use of scientific metaphors, including anthropomorphisms and science fiction, to describe host manipulation has become more and more prevalent. It is possible that the repeated use of such catchy, yet misleading words in both the popular media and the scientific literature could unintentionally hamper our understanding of the complexity and extent of host manipulation, ultimately shaping its narrative in part or in full. In this commentary, the impacts of exaggerating host manipulation are brought to light by examining trends in the use of embellishing words. By looking at key examples of exaggerated claims from widely reported host–parasite systems found in the recent scientific literature, it would appear that some of the fiction surrounding host manipulation has since become fact.

Electronic supplementary material is available online at https://doi.org/10.6084/m9.figshare.c.5136015

Men’s height preferences are responsive to gender-role ideology; women’s preferences are insensitive to it; women prefer a tall partner much more than men prefer a short partner

Gender-Role Ideology and Height Preference in Mate Selection. Hung-Lin Tao. Economics & Human Biology, October 13 2020, 100927. https://doi.org/10.1016/j.ehb.2020.100927

Highlights

• Men’s height preferences are responsive to gender-role ideology.

• Women’s height preferences are insensitive to gender-role ideology.

• Women prefer a tall partner much more than men prefer a short partner.

• Women’s height preferences are sensitive to their own characteristics.

• In marriage, gender-role ideology is not relevant to their partners’ height.

Abstract: This study used Taiwan’s Panel Study of Family Dynamics (PSFD) 2016 data to investigate the relationship between gender-role ideology and height preference in mate selection, finding that women prefer a tall partner much more than men prefer a short partner. However, when traditional gender norms prevail, men with a high levels of adherence to gender-role ideology cannot accept a female partner who is either too tall or too short. Men’s height preferences are more responsive to social norms than women’s, while women’s height preferences are more sensitive to their own demographic characteristics than men’s. The tallest and shortest female partners accepted by men with strong traditional gender-role ideology are 2.37 cm shorter and 2.21 cm taller, respectively, than men who disagree with gender norms. In marriage, gender-role ideology is not relevant to partner height, regardless of sex.

Keywords: HeightGender-role ideologyMate selection

After many years of decline in violent behavior among adolescents in several Western countries, recent official statistics indicate a possible trend change - Data from Norway

Physical Fighting and Leisure Activities among Norwegian Adolescents-Investigating Co-occurring Changes from 2015 to 2018. Lars Roar Frøyland, Anders Bakken, Tilmann von Soest. J Youth Adolesc. 2020 Nov;49(11):2298-2310. doi: 10.1007/s10964-020-01252-8. Epub May 27 2020

Abstract: After many years of decline in violent behavior among adolescents in several Western countries, recent official statistics indicate a possible trend change. So far, knowledge on how this change is related to co-occurring changes in leisure time activities is limited. Using two cross-sectional surveys from Oslo, Norway, this study found substantial increases in the prevalence of physical fighting from 2015 (N = 23,381; 51.6% girls) to 2018 (N = 25,287; 50.8% girls) in junior and senior high school. The rise in fighting was related to co-occurring changes in several leisure activities, including increasing time spent unsupervised by adults, rising digital media use, and rising cannabis use. The study emphasizes the importance of considering leisure time activities when addressing adolescent misbehavior.

Keywords: Leisure activities; Physical fighting; Time trends; Violence.

Partner dreams are not only common in persons with stable partnership (24%) but also in singles (16%); ex-partner dreams were less positive than partner dreams and quite frequent – even years after separation

Partners and ex-partners in dreams: An online survey. Michael Schredl, Naiara Cadiñanos Echevarria, Louise Saint Macary, Alexandra Francesca Weiss. International Journal of Dream Research, Vol 13, No 2 (October 2020). https://doi.org/10.11588/ijodr.2020.2.75338

Rolf Degen's take: https://twitter.com/DegenRolf/status/1315997019517972480

Abstract: Social interactions, especially with the romantic partner, are a very important part of waking life and – in line with the continuity hypothesis of dreaming – also play an important role in dreams. In total, 1695 persons (960 women, 735 men; mean age: 53.84 ± 13.99 yrs.) completed an online survey that included questions about estimating retrospectively the frequency of partner and ex-partner(s) dreams and questions about their relationship status. These estimates indicate that partner dreams are not only common in persons with stable partnership (24%) but also in singles (16%). Partnership quality was the strongest predictor of the emotional tone of partner dreams. Ex-partner dreams were less positive than partner dreams and quite frequent – even years after separation. The next step would be to collect partner and ex-partner dream reports and study the interaction between partnership and partner dreams in a longitudinal design.

The eye wants what the heart wants: Women’s preferences for male faces are associated with their preferences for personality traits

Oh, D., Grant-Villegas, N., & Todorov, A. (2020). The eye wants what the heart wants: Female face preferences are related to partner personality preferences. Journal of Experimental Psychology: Human Perception and Performance, Oct 2020. https://doi.org/10.1037/xhp0000858

Abstract: Women prefer male faces with feminine shape and masculine reflectance. Here, we investigated the conceptual correlates of this preference, showing that it might reflect women’s preferences for feminine (vs. masculine) personality in a partner. Young heterosexual women reported their preferences for personality traits in a partner and rated male faces—manipulated on masculinity/femininity—on stereotypically masculine (e.g., dominance) and feminine traits (e.g., warmth). Masculine shape and reflectance increased perceptions of masculine traits but had different effects on perceptions of feminine traits and attractiveness. While masculine shape decreased perceptions of both attractiveness and feminine traits, masculine reflectance increased perceptions of attractiveness and, to a weaker extent, perceptions of feminine traits. These findings are consistent with the idea that sex-dimorphic characteristics elicit personality trait judgments, which might in turn affect attractiveness. Importantly, participants found faces attractive to the extent that these faces elicited their preferred personality traits, regardless of gender typicality of the traits. In sum, women’s preferences for male faces are associated with their preferences for personality traits.

Famous pop songs, 1975-2017: Lyrics became darker as emotional words became less positive and more negative; swear words and sexual words tended to remain rare and to increase slightly over the decades

Blais-Rochette, C., Miranda, D., Goulet, M.-A., & Gaudreau, P. (2020). Songs as a way of listening to cultures across generations? A comparison of Canada and the United States through their famous songs from 1975 to 2017. Psychology of Aesthetics, Creativity, and the Arts, Oct 2020. https://doi.org/10.1037/aca0000347

Abstract: This study examined if there are cross-cultural and cross-generational similitudes and differences between Canada and the United States through their famous songs across 5 decades. We used the software Linguistic Inquiry and Word Count (LIWC2015; Pennebaker, Boyd, Jordan, & Blackburn, 2015a) to analyze the evolution of lyrics for songs that were nominated at the Canadian Juno Awards and the American Grammy Awards from 1975 to 2017. We targeted songs that were nominated for “bestselling single/single of the year” at the Juno and “song of the year” at the Grammy as they represent some of the most popular and respected cultural products in their respective countries. We analyzed markers of self-focus, group-focus, social connectedness, emotions (positive and negative), religion, and explicit lyrics (swearing and sexuality). Results consistently revealed more cross-cultural similarities than differences between the lyrics of Juno’s and Grammy’s songs on all our markers. However, subtle generational variations unfolded over the years. Notably, self-focus words followed different patterns in the Juno’s songs compared to the Grammy’s songs, but reached similar levels in the 2010s. Group-focus words increased in Juno’s songs but decreased in Grammy’s songs. Social connectedness words were the most present in famous songs and remained relatively stable. Song lyrics became darker as emotional words became less positive and more negative. Religious words tended to remain rare in famous songs. Swear words and sexual words tended to remain rare and to increase slightly over the decades. Findings are discussed through a Cultural × Generational perspective. 

Largest‐ever mega‐analysis: Already from age one, males show greater variability of brain structures than females, being more likely to fall in the extremes

Greater male than female variability in regional brain structure across the lifespan. Lara M Wierenga et al. Human Brain Mapping, October 12 2020. https://doi.org/10.1002/hbm.25204

Rolf Degen's take: https://twitter.com/DegenRolf/status/1315991008581169154

Abstract: For many traits, males show greater variability than females, with possible implications for understanding sex differences in health and disease. Here, the ENIGMA (Enhancing Neuro Imaging Genetics through Meta‐Analysis) Consortium presents the largest‐ever mega‐analysis of sex differences in variability of brain structure, based on international data spanning nine decades of life. Subcortical volumes, cortical surface area and cortical thickness were assessed in MRI data of 16,683 healthy individuals 1‐90 years old (47% females). We observed significant patterns of greater male than female between‐subject variance for all subcortical volumetric measures, all cortical surface area measures, and 60% of cortical thickness measures. This pattern was stable across the lifespan for 50% of the subcortical structures, 70% of the regional area measures, and nearly all regions for thickness. Our findings that these sex differences are present in childhood implicate early life genetic or gene‐environment interaction mechanisms. The findings highlight the importance of individual differences within the sexes, that may underpin sex‐specific vulnerability to disorders.

4 DISCUSSION

In this study, we analyzed a large lifespan sample of neuroimaging data from 16,683 participants spanning nine decades of life starting at birth. Results confirmed the hypothesis of greater male variability in brain structure (Forde et al. 2020; Ritchie et al. 2018; Wierenga et al. 2018, 2019). Variance differences were more pronounced for subcortical volumes and regional cortical surface area than for regional cortical thickness. We also corroborated prior findings of greater male brain structural variance at both upper and lower tails of brain measures (Wierenga et al. 2018). These variance effects seem to describe a unique aspect of sex differences in the brain that does not follow the regional pattern of mean sex differences. A novel finding was that sex differences in variance appear stable across the lifespan for around 50% of subcortical volumes, 70% of cortical surface area measures and almost all cortical thickness measures. Unexpectedly, regions with significant change in variance effects across the age range showed decreasing variance differences between the sexes with increasing age. Finally, we observed greater male inter‐regional homogeneity for cortical thickness, but not for surface area or subcortical volumes, partly replicating prior results of greater within‐subject homogeneity in the male brain (Wierenga et al. 2018). Unexpectedly, subcortical regions showed stronger interregional correlation in females than in males.

Greater male variance was most pronounced in brain regions involved in planning, regulation and inhibition of motor movements (pallidum, right inferior parietal cortex and paracentral region), episodic memory (hippocampus), and multimodal sensory integration (thalamus) (Aron, Robbins, and Poldrack 2004; Burgess, Maguire, and O'Keefe 2002; Grillner et al. 2005). In addition, the early presence of sex differences in brain structural variability may be indicative of genetic effects, in line with findings in a pediatric sample (Wierenga et al. 2018). We also observed that sex differences in structural variation are either stable or may reduce in old age. Longitudinal designs are, however, needed to address the mechanisms underlying this observation.

The expression of greater male variability in both upper and lower tails of the distribution may be related to architectural and geometric constraints that are critical for a delicate balance for effective local‐global communication. For example, neurons only partly regulate their size, and the number of neural connections does not vary strongly with neocortical size across species (Stevens 1989). Although axon size and myelin can compensate firing rates in larger brains by speeding up conduction time, there is a limited energy budget to optimize both volume and conduction time (Buzsáki, Logothetis, and Singer 2013). As such, extreme brain structure (in both directions) may come at a cost. This is in line with recent findings that show that extreme neural activity patterns may induce suboptimal expressions of mental states (Northoff and Tumati 2019). Interestingly, it has been found that individuals with autism spectrum disorder show atypical patterns of brain structure and development in both the upper and lower range (Zabihi et al. 2019), suggesting a possible link between greater male variability and vulnerability for developmental disorders (see also Alnæs et al. 2019)). Together with our findings, this opens up new approaches to understanding sex biased developmental disorders, beyond group‐level mean differences.

Although most results showed stable sex differences with increasing age, half of the subcortical regions and a quarter of the cortical surface area measures showed decreasing sex differences in variance. What stands out is that in all these regions, sex differences in variance were largest in young compared to older age. This is indicative of early mechanisms being involved. Furthermore, for subcortical regions, the patterns showed larger volumetric increases in females then in males. For surface area, interaction effects showed mostly stable variance across age in females, but decreases in variability in males. The observation that there were no significant quadratic interactions makes it unlikely that pubertal hormones may affect greater male variance. Yet, the decrease in male variance in older age, may be indicative of environmental effects later in life. Alternative explanation may be the larger number of clinical or even death rates in males that may lead to some sex difference in survival (Chen et al. 2008; Ryan et al. 1997).

Factors underlying or influencing sex differences in the brain may include sex chromosomes, sex steroids (both perinatal or pubertal), and the neural embedding of social influences during the life span (Dawson, Ashman, and Carver 2000). Although we could not directly test these mechanisms, our findings of greater male variance, that are mostly stable across age, together with the greater male inter‐regional homogeneity for cortical thickness are most in line with the single X‐chromosome expression in males compared to the mosaic pattern of X‐inactivation in females (Arnold 2012). Whereas female brain tissue shows two variants of X‐linked genes, males only show one. This mechanism may lead to increased male vulnerability, as is also seen for a number of rare X‐linked genetic mutations (Chen et al. 2008; Craig, Haworth, and Plomin 2009; Johnson, Carothers, and Deary 2009; Reinhold and Engqvist 2013; Ryan et al. 1997). None of the other sex effects mentioned above predict these specific inter and intra‐individual sex differences in brain patterns. Future studies are, however, needed to directly test these different mechanisms. Furthermore, the observation that greater male homogeneity was only observed in cortical thickness, but not cortical surface area or subcortical volumes, may speculatively indicate that X‐chromosome related genetic mechanisms may have the largest effect on cortical thickness measures.

This paper has several strengths including its sample size, the age range spanning nine decades, the inclusion of different structural measures (subcortical volumes and cortical surface area and thickness) and the investigation of variance effects. These points are important, as most observed mean sex differences in the brain are modest in size (Joel and Fausto‐Sterling 2016). We were able to analyze data from a far larger sample than those included in recent meta‐analyses of mean sex differences (Marwha et al. 2017; Ruigrok et al. 2014; Tan et al. 2016), and a very wide age range covering childhood, adolescence, adulthood and senescence. The results of this study may have important implications for studies on mean sex differences in brain structure, as analyses in such studies typically assume that group variances are equal, which the present study shows might not be tenable. This can be particularly problematic for studies with small sample sizes (Rousselet et al. 2017).

The current study has some limitations. First, the multi‐site sample was heterogeneous and specific samples were recruited in different ways, not always representative of the entire population. Furthermore, although structural measures may be quite stable across different scanners, the large number of sites may increase the variance in observed MRI measures, but this would be unlikely to be systematically biased with respect to age or sex. In addition, variance effects may change in non‐linear ways across the age‐range. This may be particularly apparent for surface area and subcortical volume measures, as these showed pronounced non‐linear developmental patterns through childhood and adolescence (Tamnes et al. 2017; Wierenga et al. 2018). Also, the imbalanced number of subjects across the age range may have diminished variability effects in the older part of the age range. The present study has a cross‐sectional design. Future studies including longitudinal data are warranted to further explore the lifespan dynamics of sex differences in variability in the brain. Last, one caveat may be the effect of movement on data quality and morphometric measures. As males have been shown to move more than females in the scanner (Pardoe, Kucharsky Hiess, and Kuzniecky 2016), this may have resulted in slight under estimations of brain volume and thickness measures for males (Reuter et al. 2015). Although quality control was conducted at each site using the standardized ENIGMA cortical and subcortical quality control protocols (http://enigma.ini.usc.edu/protocols/imaging-protocols/), which involve a combination of statistical outlier detection and visual quality checks and a similar number of males and females had partially missing data (52.4% males), we cannot exclude the possibility that in‐scanner subject movement may have affected the results. Nevertheless, we do not think this can explain our finding of greater male variance in brain morphometry measures, as this was seen at both the upper and lower ends of the distributions.

Brain damage robbed a patient of the ability to put himself in other people's shoes — and the ability to recognize that failure

Anosognosia for Theory of Mind deficits: a single case study and a review of the literature. alentina Pacella et al. Neuropsychologia, October 13 2020, 107641. https://doi.org/10.1016/j.neuropsychologia.2020.107641

Rolf Degen's take: 

Highlights

• Anosognosia after TBI can be selective for Theory of Mind deficits.

•Theory of Mind deficits are not secondary to executive functions impairment.

• The limbic, monitoring and attentional systems play a role in anosognosia.

Abstract: Being aware of one’s own ability to interact socially is crucial to everyday life. After a brain injury, patients may lose their capacity to understand others’ intentions and beliefs, that is, the Theory of Mind (ToM). To date, the debate on the association between ToM and other cognitive deficits (in particular executive functions and behavioural disorders) remains open and data regarding awareness of ToM deficits are meagre. By means of an ad-hoc neuropsychological battery of tests, we report on a patient who suffers from ToM deficits and is not aware of these disorders, although aware of his other symptoms. The study is accompanied by a review of the literature (PRISMA guidelines) demonstrating that ToM deficits are independent from executive functions. Furthermore, an advanced lesion analysis including tractography was executed. The results indicate that: i) ToM deficits can be specific and independent from other cognitive symptoms; ii) unawareness may be specific for ToM impairment and not involve other disorders and iii) the medial structures of the limbic, monitoring and attentional systems may be involved in anosognosia for ToM impairment.

Keywords: AnosognosiaTheory of MindDTIAwarenessFrontal Lesion

Maybe we evolved (genetically or culturally) to be insensitive to efficacy when donating because people tend not to reward efficacy but well-defined and highly observable behaviours

An evolutionary explanation for ineffective altruism. Bethany Burum, Martin A. Nowak & Moshe Hoffman. Nature Human Behaviour, Oct 12 2020. https://www.nature.com/articles/s41562-020-00950-4

Abstract: We donate billions to charities each year, yet much of our giving is ineffective. Why are we motivated to give but not to give effectively? Building on evolutionary game theory, we argue that donors evolved (genetically or culturally) to be insensitive to efficacy because people tend not to reward efficacy, as social rewards tend to depend on well-defined and highly observable behaviours. We present five experiments testing key predictions of this account that are difficult to reconcile with alternative accounts based on cognitive or emotional limitations. Namely, we show that donors are more sensitive to efficacy when helping (1) themselves or (2) their families. Moreover, (3) social rewarders don’t condition on efficacy or other difficult-to-observe behaviours (4, 5), such as the amount donated.

When men have more bargaining power (e.g., higher earnings), they manage to attend opera, ballet and other dance performances, which are more frequently attended by women than by men, less frequently

Battle of the ballet household decisions on arts consumption. Caterina Adelaide Mauri & Alexander Friedrich Wolf. Journal of Cultural Economics, Oct 9 2020. https://link.springer.com/article/10.1007/s10824-020-09395-z

Rolf Degen's take: https://twitter.com/DegenRolf/status/1315896750230700032

Abstract: Women and men differ in their tastes for the performing arts. Gender differences have been shown to persist after accounting for socioeconomic factors. This paper uses this difference to shed light on how decisions on arts consumption are made in households. Based on relatively recent theoretical developments in the literature on household decision-making, we use three different so-called distribution factors to show for the first time that the relative bargaining power of spouses affects their arts consumption. Using a sample from the US Current Population Survey, which includes data on the frequency of visits to cultural activities, we regress attendance on a range of socioeconomic variables using a count data model. The distribution factors consistently affect attendance by men at events such as the opera, ballet and other dance performances, which are more frequently attended by women than by men. We conclude that when men have more bargaining power, they tend to attend such events less frequently.

The salubrious effects of prosocial behavior in the short term are not likely due to the inhibition of cellular aging (at least as indexed by telomere length)

Fritz, Megan M., Lisa C. Walsh, Steve Cole, Elissa Epel, and Sonja Lyubomirsky. 2020. “Kindness and Cellular Aging: A Pre-registered Experiment Testing the Effects of Prosocial Behavior on Telomere Length and Well-being.” PsyArXiv. October 12. doi:10.31234/osf.io/d6wtn

Abstract

Objective: Prosocial behavior can improve psychological well-being and physical health. However, the underlying biological mechanisms that mediate the relationship between prosociality and health remain unclear. In this pre-registered experiment, we tested whether a 4-week kindness intervention could slow leukocyte telomere shortening and increase well-being.

Methods: Community adults (N = 230) were randomly assigned to complete 1 of 3 activities, each week for 4 weeks: to perform 3 kind acts for other people, to perform 3 kind acts for themselves, or to list daily activities. At baseline and post-intervention, participants came to the lab to provide a small dried blood spot (DBS) sample via finger prick for analysis of telomere length. Participants completed psychological measures (e.g., loneliness, life satisfaction) at baseline, post-intervention, and at the 2-week follow up.

Results: Participants who performed kind acts for others did not demonstrate hypothesized changes in telomere length, nor in well-being, relative to controls. Exploratory analyses revealed that, relative to controls, participants who did kind acts for others showed reductions in loneliness through the 2-week follow up.

Conclusions: The salubrious effects of prosocial behavior in the short term are not likely due to the inhibition of cellular aging (at least as indexed by telomere length). However, extending kindness to others holds promise as a plausible intervention to alleviate the public health crisis of loneliness.

China: The results reveal an inverted U-shaped relationship between BMI and happiness, with obesity associated with happiness through physical appearance, health, and income

How is obesity associated with happiness? Evidence from China. Yiwei Liu, Ling Xu, Aaron Hagedorn. Journal of Health Psychology, October 11, 2020. https://doi.org/10.1177/1359105320962268

Rolf Degen's take: https://twitter.com/DegenRolf/status/1315715377553444864

Abstract: Happiness is a universal goal that people pursue. Studies of the relationship between obesity and happiness have shown mixed findings. It is uncertain whether an optimum BMI level exists and at what level obesity interferes or interacts with happiness. Guided by the Circle of Discontent Theory, we examined the relationship between obesity and happiness among Chinese residents using the 2014 China Family Panel Studies data. The results reveal an inverted U-shaped relationship between BMI and happiness, with obesity associated with happiness through physical appearance, health, and income. The socioeconomic conditions for the appropriate weight to achieve happiness are discussed.

Keywords: China, circle of discontent theory, happiness, health, income, obesity, physical appearance

People high in communion, to make others happy or to display their niceness, are particularly keen to share 'happy thoughts'

Altay, Sacha, and Hugo Mercier. 2020. “Happy Thoughts: The Role of Communion in Accepting and Sharing Epistemically Suspect Beliefs.” PsyArXiv. October 12. doi:10.31234/osf.io/3s4nr

Rolf Degen's take: https://twitter.com/DegenRolf/status/1315682270196490253

Abstract: Why are some epistemically suspect beliefs so popular? People high in communion, either because they want to make others happy, or because they want to display their niceness, might be particularly keen to share ‘happy thoughts,’ beliefs that might make others happy, even if they are epistemically suspect—for instance, that naturopathy works, or that heaven exists. Across six experiments (N = 1596) we found that: (i) people who self-describe as being high on communion (i.e., nice, kind) are more likely to believe and share happier epistemically suspect beliefs, by contrast with people who self-describes as being high on agency (i.e., competent, dominant); (ii) people prefer to share happier beliefs when wishing to appear nice and kind rather than competent and dominant; (iii) sharing happier beliefs does lead to being perceived as nicer and kinder; and (iv) sharing happier beliefs leads to being perceived as less dominant. We also found a consistent positive bias independent of participants’ personality, with happier beliefs being more likely to be shared and believed. Overall, these results suggest that some happy epistemically suspect beliefs could become culturally successful because they allow their sender to signal niceness and kindness.

The more-men-more-violence association holds particularly for male violence against other men, is insignificant for violence against women, & the association is significant among childless men, but not among fathers

Are skewed sex ratios associated with violent crime? A longitudinal analysis using Swedish register data. Andreas Filser et al. Evolution and Human Behavior, October 12 2020. https://doi.org/10.1016/j.evolhumbehav.2020.10.001

Abstract: There is widespread concern in both the popular and academic literature that a surplus of men in a population intensifies mating competition between men, particularly unpartnered men, resulting in increased violence towards both men and women. Recent contributions challenge this perspective and argue that male mating competition and levels of violence will be higher when sex ratios are female-skewed. Existing empirical evidence remains inconclusive. We argue that this empirical ambiguity results from analyses of aggregate-level data, which put inferences at risk of ecological fallacies. Our analysis circumvents such problems by using individual-level, longitudinal demographic register and police data for the Stockholm metropolitan area, Sweden (1990–2003, n = 758,498). These data allow us to investigate the association between municipality-level sex ratios and violent offending (homicide, assault, threat, and sexual crimes) while adjusting for sociodemographic factors. Results suggest that aggregated offending rates are negatively associated with male-skewed sex ratios, whereas individual-level violent offending correlates positively with male-skews. We find that the more-men-more-violence association holds particularly for male violence against other men, but is insignificant for violence against women. Moreover, the association is significant among childless men, but not among fathers. However, robustness checks question the causality of these associations. Female violent offending is positively, albeit due to a low number of cases, insignificantly associated with male-skews. Moreover, both male and female non-violent offending is higher in male-skewed municipalities. We discuss the implications with regard to the theoretical debate and problems of unobserved heterogeneity in the sex ratio literature.

Keywords: Sex ratioViolent crimeMating marketSweden

Synthetic voice composites generated by averaging multiple (same gender) individual voices (short syllables) are perceived as increasingly attractive with the number of voices averaged

Belin P. (2021) On Voice Averaging and Attractiveness. In: Weiss B., Trouvain J., Barkat-Defradas M., Ohala J.J. (eds) Voice Attractiveness. Prosody, Phonology and Phonetics. Springer, Singapore, Oct 11 2020. https://doi.org/10.1007/978-981-15-6627-1_8

Rolf Degen's take: https://twitter.com/DegenRolf/status/1315642311196520449

Abstract: Several experiments investigating the perceptual, acoustical and neural bases of the ‘voice attractiveness averaging phenomenon’ are briefly summarized. We show that synthetic voice composites generated by averaging multiple (same gender) individual voices (short syllables) are perceived as increasingly attractive with the number of voices averaged. This phenomenon, independent of listener or speaker gender and analogous to a similar effect in the visual domain for face attractiveness, is explained in part by two acoustical correlates of averaging: reduced ‘Distance-to-Mean’, as indexed by the Euclidean distance between a voice and its same-gender population average in f0-F1 space and increased voice ‘texture smoothness’ as indexed by increased harmonics-to-noise ratio (HNR). These two acoustical parameters co-vary with perceived attractiveness and manipulating them independently of one another also affects attractiveness ratings. The neural correlates of implicitly perceived attractiveness consist in a highly significant negative correlation between attractiveness and fMRI signal in large areas of bilateral auditory cortex, largely overlapping with the Temporal Voice Areas, as well as inferior prefrontal cortex: more attractive voices elicit less activity in these regions. While the correlations in auditory areas were largely explained by distance-to-mean and HNR, inferior prefrontal areas bilaterally were observed even after co-varying out variance explained by these acoustical parameters, suggesting a role as abstract voice attractiveness evaluators.

Keywords: Averageness Aperiodicity Distance-to-mean Distinctiveness Pitch Formant dispertion

Spouses’ faces are similar but do not become more similar 20-69 years later

Spouses’ faces are similar but do not become more similar with time. Pin Pin Tea‑makorn & Michal Kosinski. Scientific Reports, Oct 12 2020. https://doi.org/10.1038/s41598-020-73971-8

The widely disseminated convergence in physical appearance hypothesis posits that long-term partners’ facial appearance converges with time due to their shared environment, emotional mimicry, and synchronized activities. Although plausible, this hypothesis is incompatible with empirical fndings pertaining to a wide range of other traits—such as personality, intelligence, attitudes, values, and well-being—in which partners show initial similarity but do not converge over time. We solve this conundrum by reexamining this hypothesis using the facial images of 517 couples taken at the beginning of their marriages and 20 to 69 years later. Using two independent methods of estimating their facial similarity (human judgment and a facial recognition algorithm), we show that while spouses’ faces tend to be similar at the beginning of marriage, they do not converge over time, bringing facial appearance in line with other personal characteristics.

Discussion

We do not fnd support for the widely disseminated convergence in physical appearance hypothesis: Spouses’ faces are similar but do not converge with time. Tis brings facial appearance in line with other traits—such as interests, personality, intelligence, attitudes, values, and well-being—which show initial similarity but do not converge over time.

This study has several limitations. First, we used publicly available images and thus could not control for variance in image properties and self-presentation (such as grooming, facial expression, or biases in selecting images to be publicly shared online). Yet, according to the convergence in physical appearance hypothesis, these factors should amplify the convergence rather than obscure it. Spouses’ tendency to occupy the same environments, engage in the same activities, eat the same food, and—in particular—mimic each other’s emotional expressions should result in convergence in their self-presentation behaviors, and thus more (and not less) similar public facial images. Second, we did not record or control for judges’ age and ethnicity and thus the extent to which their judgments might have been afected by the own-age36 and own-ethnicity37 biases (people’s lower sensitivity when judging the similarity of faces of other ages and ethnic groups). Yet, while the own-ethnicity bias could add noise to our measurements, it is unlikely to moderate the change in similarity over time, as participants’ ethnicity was constant. Also, while the U.S. AMT workers tend to be young38, they were as good at ranking the similarity of faces of young people (taken several decades ago) as the faces of older people (taken more recently). Furthermore, those and other risks to the judges’ accuracy were counterbalanced by the use of two independent measures of facial similarity (human judges and VGGFace2) and the relatively large sample size, enabling the detection of a change in human rankings as small as Δ=0.17 (with 80% power, α=0.001), an equivalent of one in six judges increasing a spouse’s rank by just one position. Finally, the validity of our approach and dataset are supported by the successful replication of the well-established efect of people’s tendency to marry similar others (i.e., homogamy).

While the rejection of the convergence in physical appearance hypothesis is surely not as exciting or as citeworthy as its counterfactual, it solves one of the major conundrums of psychological science and brings us closer to understanding factors predisposing people to form and maintain long-term romantic relationships.