Monday, December 27, 2021

The energetics of uniquely human subsistence strategies: Efficiency leads to leisure, allowing our ancestors to spend more time in contexts that facilitated social learning and cultural development

The energetics of uniquely human subsistence strategies. Thomas Kraft et al. Science Dec 24 2021, Vol 374, Issue 6575. https://www.science.org/doi/abs/10.1126/science.abf0130

Efficiency leads to leisure

Humans are animals—merely another lineage of great apes. However, we have diverged in significant ways from our ape cousins and we are perennially interested in how this happened. Kraft et al. looked at energy intake and expenditure in modern hunter-gatherer societies and great apes. They found that we do not spend less energy while foraging or farming, but we do acquire more energy and at a faster rate than our ape cousins. This difference may have allowed our ancestors to spend more time in contexts that facilitated social learning and cultural development. —SNV


Structured Abstract

INTRODUCTION: Relative to other great apes, humans have large brains, long life spans, higher fertility and larger neonates, and protracted periods of childhood dependency and development. Although these traits constitute the unique human life history that underlies the ecological success of our species, they also require human adults to meet extraordinarily high energetic demands. Determining how human subsistence strategies have met such extreme energy needs, given time and energy expenditure constraints, is thus key to understanding the origins of derived human traits.

RATIONALE: Two major transitions in hominin subsistence strategies are thought to have elevated energy capture: (i) the development of hunting and gathering ~2.5 million years ago, which coincided with brain enlargement and extended postnatal growth, and (ii) the rise of agriculture ~12,000 years ago, which was accompanied by substantial increases in fertility and population densities. These transitions are associated with the exploitation of novel food sources, but it is not clear how the energy and time budgets of early human foragers and farmers shifted to accommodate expensive traits. Some evolutionary reconstructions contend that economical locomotion, cooperation, the use of sophisticated tools, and eventually agriculture increased energy efficiency (i.e., energy gained versus energy spent), beyond that of other great apes. Alternatively, unique human subsistence strategies may reduce time and improve yield, increasing return rates (i.e., energy gained versus time spent).

To test these ideas, we compared subsistence costs (energy and time) and energy acquisition among wild orangutans, gorillas, and chimpanzees with high-resolution data on total energy expenditure, food acquisition, and time allocation, collected among Tanzanian hunter-gatherers (Hadza) and Bolivian forager-horticulturalists (Tsimane). Both populations actively forage (hunt, gather), whereas the Tsimane also practice slash-and-burn horticulture, which permits exploration of further changes in the energetics of subsistence associated with farming. We also assembled a global subsistence energetics database of contemporary hunter-gatherers and horticulturalists.


RESULTS: Relative to other great apes, human hunter-gatherers and horticulturalists spend more energy daily on subsistence, and they achieve similar energy efficiencies despite having more economical locomotion and using sophisticated technologies. In contrast, humans attain much greater return rates, spending less time on subsistence while acquiring more energy per hour. Further, horticulture is associated with higher return rates than hunting and gathering, despite minimal differences in the amount of time devoted to subsistence. Findings from our detailed study of the Hadza and Tsimane were consistent with those from the larger cross-cultural database of subsistence-level societies. Together, these results support prior evidence that the adoption of farming could have been motivated by greater gains per time spent working, and refute the notion that farming lifestyles are necessarily associated with increased labor time.

CONCLUSION: These findings revise our understanding of human energetics and evolution, indicating that humans afford expanded energy budgets primarily by increasing rates of energy acquisition, and not through energy-saving adaptations (such as economical bipedalism or sophisticated tool use) that decrease overall costs. Relative to other great apes, human subsistence strategies are characterized by high-intensity, high-cost extractive activities and expanded day ranges that provide more calories in less time. These results suggest that energy gained from improvements in efficiency throughout human evolution were primarily channeled toward further increasing foraging intensity rather than reducing the energetic costs of subsistence. Greater energetic gains per unit time are the reward for humans’ intense and behaviorally sophisticated subsistence strategies. Humans’ high-cost but high-return strategy is ecologically risky, and we argue that it was only possible in the context of increased cooperation, intergenerational food sharing, and a division of labor. We contend that the time saved by human subsistence strategies provided more leisure time for social interaction and social learning in central-place locations, which is critical for cumulative cultural evolution.

Abstract: The suite of derived human traits, including enlarged brains, elevated fertility rates, and long developmental periods and life spans, imposes extraordinarily high energetic costs relative to other great apes. How do human subsistence strategies accommodate our expanded energy budgets? We found that relative to other great apes, human hunter-gatherers and subsistence farmers spend more energy but less time on subsistence, acquire substantially more energy per hour, and achieve similar energy efficiencies. These findings revise our understanding of human energetic evolution by indicating that humans afford expanded energy budgets primarily by increasing rates of energy acquisition, not through energy-saving adaptations such as economical bipedalism or sophisticated tool use that decrease subsistence costs and improve the energetic efficiency of subsistence. We argue that the time saved by human subsistence strategies provides more leisure time for social interaction and social learning in central-place locations and would have been critical for cumulative cultural evolution.


Choosing from too many options can lead to suboptimal results (choice overload); monkeys do not experience choice overload

No evidence of the choice overload effect in a computerized paradigm with rhesus macaques (Macaca mulatta) and capuchin monkeys (Sapajus apella). Maisy D. Englund, Michael J. Beran. Behavioural Processes, Volume 194, January 2022, 104545. https://doi.org/10.1016/j.beproc.2021.104545

Highlights

• Choosing from too many options can lead to suboptimal results (choice overload).

• This study is the first to test nonhuman animals on the choice overload effect.

• Results indicate that monkeys do not experience choice overload with this paradigm.

• The methodology used here provides insights for future avenues of research.

Abstract: Given the choice, people are often drawn toward more options over fewer options in decision-making scenarios. However, mounting evidence indicates that sometimes, choosing from large arrays can result in suboptimal outcomes. The tendency to be overwhelmed, regretful, or less satisfied with a choice when there are many options to choose from is called choice overload. This effect has been well-studied in adult humans, but comparative research, such as with nonhuman primates, is lacking, despite the fact that such choice behavior may be related to general aspects of cognition that underlie behaviors such as foraging in the wild. In addition, research with monkeys can shed light on whether choice overload is a human-unique phenomenon that may be driven by sociocultural factors, or whether this effect may be shared more broadly among mammals. This experiment tested whether monkeys were susceptible to choice overload effects by using a computerized paradigm in which monkey subjects could choose from three, six, or nine task options. No evidence of choice overload was found for monkeys, although this may have been due to methodological limitations that are described.

Keywords: Choice overloadComparative cognitionNonhuman primatesOverchoiceParadox of choice


Unpleasant odors are registered in the brain particularly fast and at an early stage of olfactory information processing

Localizing the human brain response to olfactory stimulation: A meta-analytic approach. A.Torske, K. Koch, S. Eickhoff, J. Freiherr. Neuroscience & Biobehavioral Reviews, December 27 2021. https://doi.org/10.1016/j.neubiorev.2021.12.035

Highlights

•  This paper provides the scientific community with an all-encompassing, up-to-date perspective on the human olfactory cortex through the quantification of all relevant and available data by implementing a robust meta-analytic approach.

•  The human olfactory cortex exhibits distinct activation patterns for different odor categories.

•  The neural underpinnings of the human sense of smell allows for a deeper understanding of human behavior through the extraction of valuable odorous information from the environment.

Abstract: The human sense of smell and the ability to detect and distinguish odors allows for the extraction of valuable information from the environment, thereby driving human behavior. Not only can the sense of smell help to monitor the safety of inhaled air, but it can also help to evaluate the edibility of food. Therefore, in an effort to further our understanding of the human sense of smell, the aim of this meta-analysis was to provide the scientific community with activation probability maps of the functional anatomy of the olfactory system, in addition to separate activation maps for specific odor categories (pleasant, food, and aversive odors). The activation likelihood estimation (ALE) method was utilized to quantify all relevant and available data to perform a formal statistical analysis on the inter-study concordance of various odor categories. A total of 81 studies (108 contrasts, 1053 foci) fulfilled our inclusion criteria. Significant ALE peaks were observed in all odor categories in brain areas typically associated with the functional neuroanatomy of olfaction including the piriform cortex, amygdala, insula, and orbitofrontal cortex, amongst others. Additional contrast analyses indicate clear differences in neural activation patterns between odor categories.

Keywords: Olfactory cortexSmellNeuroimagingActivation likelihood estimationMeta-analysis


National Latino and Asian American Study: Extramarital sex associated with marital satisfaction, religious attendance; odds of men reporting engaging in extramarital sex was 3.52 times greater than odds of women

Diversity in the prevalence and correlates of extramarital sex in a probability sample of Latino adults. Sanchez, L., Whisman, M. A., Hughes, J. A., & Gordon, K. C. (2021). Diversity in the prevalence and correlates of extramarital sex in a probability sample of Latino adults. Journal of Family Psychology, Dec 2021. https://doi.org/10.1037/fam0000942

Abstract: Individuals from different Spanish-speaking countries are often combined into a single Latino group. However, this group is diverse, with immigrants and naturalized citizens coming from multiple countries. The present study was conducted to (a) examine potential differences in the annual prevalence of extramarital sex as a function of cultural group (Mexican, Cuban, Puerto Rican, or other Latino) and nativity (born inside or outside the United States) and (b) identify explanations for any observed differences in the prevalence of extramarital sex, drawing on known correlates of extramarital sex and other psychosocial constructs that may be associated with cultural group or nativity that could account for such associations. Results from the National Latino and Asian American Study, a probability sample of Latinos in the United States, indicated that the annual prevalence of extramarital sex was significantly higher among (a) Puerto Ricans relative to Mexicans and (b) foreign-born individuals relative to those born in the United States. Probability of extramarital sex was significantly associated with marital satisfaction and frequency of religious attendance, but these variables did not account for the subgroup differences in the prevalence of extramarital sex. Marital adjustment, acculturation (English proficiency and use), enculturation (ethnic identity), and family cohesion were not significantly associated with probability of extramarital sex. Results underscore the need for continued research on understanding subgroup differences in the prevalence of extramarital sex within the diverse Latino community and identifying characteristics that account for such differences.


Sunday, December 26, 2021

Lost in Math: How Beauty Leads Physics Astray /1

Chp 2, What a Wonderful World, in Sabine Hossenfelder's Lost in Math: How Beauty Leads Physics Astray. Basic Books, NY. 2018.

[Commenting on J Kepler changing his mind, and accepting that it appears to be the planets' orbits around the Sun is better described as ellipses, not circles...]

He received criticism in particular from Galileo Galilei (1564–1641), who believed that “only circular motion can naturally suit bodies which are integral parts of the universe as constituted in the best arrangement.”2 Another astronomer, David Fabricius (1564–1617), complained that “with your ellipse you abolish the circularity and uniformity of the motions, which appears to me the more absurd the more profoundly I think about it.” Fabricius, as many at the time, preferred to amend the planetary orbits by adding “epicycles,” which were smaller circular motions around the already circular orbits. “If you could only preserve the perfect circular orbit and justify your elliptic orbit by another little epicycle,” Fabricius wrote to Kepler, “it would be much better.”3


[Later in the chapter...]

[...] Werner Heisenberg, one of the founders of quantum mechanics, boldly believed that beauty has a grasp on truth: “If nature leads us to mathematical forms of great simplicity and beauty we cannot help thinking that they are ‘true,’ that they reveal a genuine feature of nature.”15 As his wife recalls:

One moonlit night, we walked over the Hainberg Mountain, and he was completely enthralled by the visions he had, trying to explain his newest discovery to me. He talked about the miracle of symmetry as the original archetype of creation, about harmony, about the beauty of simplicity, and its inner truth. 16

Beware the moonlight walks with theoretical physicists—sometimes enthusiasm gets the better of us.


Cognitive uncertainty explains various core empirical regularities, such as why people often appear very impatient, why per-period impatience is smaller over long than over short horizons, why choices frequently violate transitivity, etc

Cognitive Uncertainty in Intertemporal Choice. Benjamin Enke & Thomas Graeber. NBER Working Paper 29577, DOI 10.3386/w29577. December 2021. https://www.nber.org/papers/w29577

Abstract: This paper studies the relevance of cognitive uncertainty – subjective uncertainty over one's utility-maximizing action – for understanding and predicting intertemporal choice. The main idea is that when people are cognitively noisy, such as when a decision is complex, they implicitly treat different time delays to some degree alike. By experimentally measuring and manipulating cognitive uncertainty, we document three economic implications of this idea. First, cognitive uncertainty explains various core empirical regularities, such as why people often appear very impatient, why per-period impatience is smaller over long than over short horizons, why discounting is often hyperbolic even when the present is not involved, and why choices frequently violate transitivity. Second, impatience is context-dependent: discounting is substantially more hyperbolic when the decision environment is more complex. Third, cognitive uncertainty matters for choice architecture: people who are nervous about making mistakes are twice as likely to follow expert advice to be more patient.


9 Discussion

Contribution. Much of behavioral economics views intertemporal choice, and famous empirical regularities, as largely determined by non-standard discount functions (preferences). This paper argues for and empirically documents an important role of cognitive noise and complexity for intertemporal decision-making. An innovation of our study is that we directly measure and exogenously manipulate cognitive noise through self-reported cognitive uncertainty. Using this tool, we document that a large share of short-run impatience and hyperbolic discounting are driven by bounded rationality and cognitive noise, rather than impatient preferences. These insights matter not just from a scientific perspective but arguably have real economic implications. On the intensive margin of decision-making, hyperbolic discounting depends on complexity. On the extensive margin, cognitively uncertain people welcome the advice of experts even when those experts don’t know their preferences. While we emphasize throughout the paper that cognitive noise is complementary to (rather than replaces) taste-based present bias, we have shown that cognitive noise provides a better account of many of key economic phenomena that are often ascribed to present bias. In all, we interpret these results as providing some of the first direct empirical evidence that cognitive noise and cognitive uncertainty are relevant for a broad set of economic aspects of intertemporal choice.

Link to cognitive effects in intertemporal choice research. We conjecture that our account of cognitive uncertainty provides a rationale for extant empirical findings about “cognitive” effects in intertemporal choice research. The perhaps most widely-known result on cognition and intertemporal choice is that, if the time delay is relatively short, a lower availability of cognitive resources is associated with less patient decisions. At the same time, Ebert (2001) presents evidence that suggests that, over long horizons, a lower availability of resources makes people more patient. Our account of the link between inelasticity and cognitive uncertainty reconciles this somewhat puzzling combination of results. 

Moreover, Cubitt et al. (2018) present intriguing evidence that people’s decisions are much less sensitive to variation in the time delay when intertemporal decisions involve cross-domain comparisons (car now vs. vacation later) than when they only concern within-domain comparisons (car now vs. nicer car later). While no preferences-based intertemporal model predicts such effects, we conjecture that they are driven by higher cognitive noisiness in cross-domain comparisons.

Limitations. Our paper does not purport to explain nearly all intertemporal choice anomalies. One regularity that our study does not address are well-known framing effects, such as the speed-up / delay asymmetry (Loewenstein and Prelec, 1992) or date / delay effects (Read et al., 2005). At the same time, we do conjecture a potential link between such framing effects and our work: if one choice option is presented to people as the default that they can “speed up” at a cost, it seems plausible that people use that option as a cognitive default. Based on this idea, we conjecture that speed-up / delay asymmetries are more pronounced when cognitive uncertainty is high. More generally, this conjecture highlights that further research is needed to understand potential cognitive default actions. In this paper, we estimate the default action to be “intermediate,” which is consistent with various documentations of central tendency effects in cognitive psychology. Yet, it is important to note that the specific intertemporal choice context we study is one with which people have little or no experience. Future research will explore how potential cognitive default actions depend on experience and contextual influences.


The rise and fall of rationality in language

The rise and fall of rationality in language. Marten Scheffer, Ingrid van de Leemput, Els Weinans, and  View ORCID ProfileJohan Bollen. Proceedings of the National Academy of Sciences, December 21, 2021 118 (51) e2107848118; https://doi.org/10.1073/pnas.2107848118

Significance: The post-truth era has taken many by surprise. Here, we use massive language analysis to demonstrate that the rise of fact-free argumentation may perhaps be understood as part of a deeper change. After the year 1850, the use of sentiment-laden words in Google Books declined systematically, while the use of words associated with fact-based argumentation rose steadily. This pattern reversed in the 1980s, and this change accelerated around 2007, when across languages, the frequency of fact-related words dropped while emotion-laden language surged, a trend paralleled by a shift from collectivistic to individualistic language.

Abstract: The surge of post-truth political argumentation suggests that we are living in a special historical period when it comes to the balance between emotion and reasoning. To explore if this is indeed the case, we analyze language in millions of books covering the period from 1850 to 2019 represented in Google nGram data. We show that the use of words associated with rationality, such as “determine” and “conclusion,” rose systematically after 1850, while words related to human experience such as “feel” and “believe” declined. This pattern reversed over the past decades, paralleled by a shift from a collectivistic to an individualistic focus as reflected, among other things, by the ratio of singular to plural pronouns such as “I”/”we” and “he”/”they.” Interpreting this synchronous sea change in book language remains challenging. However, as we show, the nature of this reversal occurs in fiction as well as nonfiction. Moreover, the pattern of change in the ratio between sentiment and rationality flag words since 1850 also occurs in New York Times articles, suggesting that it is not an artifact of the book corpora we analyzed. Finally, we show that word trends in books parallel trends in corresponding Google search terms, supporting the idea that changes in book language do in part reflect changes in interest. All in all, our results suggest that over the past decades, there has been a marked shift in public interest from the collective to the individual, and from rationality toward emotion.

Keywords: languagerationalitysentimentcollectivityindividuality

Comments by Alex Tabarrok The Rise and Decline of Thinking over Feeling - Marginal REVOLUTIONThe authors blame the change in language towards feelings on the failure of "neo-liberalism" which seems dubious and without plausible mechanism. If anything, I would put the causality the other way. A more plausible explanation is more female writers and the closely related feminization of culture.


Potential Drivers

Inferring the drivers of this stark pattern necessarily remains speculative, as language is affected by many overlapping social and cultural changes. Nonetheless, it is tempting to reflect on a few potential mechanisms. One possibility when it comes to the trends from 1850 to 1980 is that the rapid developments in science and technology and their socioeconomic benefits drove a rise in status of the scientific approach, which gradually permeated culture, society, and its institutions ranging from the education to politics. As argued early on by Max Weber, this may have led to a process of “disenchantment” as the role of spiritualism dwindled in modernized, bureaucratic, and secularized societies (2122).

What precisely caused the observed stagnation in the long-term trend around 1980 remains perhaps even more difficult to pinpoint. The late 1980s witnessed the start of the internet and its growing role in society. Perhaps more importantly, there could be a connection to tensions arising from neoliberal policies which were defended on rational arguments, while the economic fruits were reaped by an increasingly small fraction of societies (2325).

In many languages the trends in sentiment- and intuition-related words accelerate around 2007 (SI Appendix, section 9). One possible explanation could be that the standards for inclusion in Google Books shifted from “being in a library Google had an agreement with” to “from a publisher that directly deposited with Google” after 2004 to 2007, thus affecting the corpus composition. The 2007 shift also coincides with the global financial crisis which may have had an impact. However, earlier economic crises such as the Great Depression (1929 to 1939) did not leave discernable marks on our indicators of book language. Perhaps significantly, 2007 was also roughly the start of a near-universal global surge of social media. This may be illustrated by plotting the dynamics of the word “Facebook” as a marker alongside the frequency of a set of intuition and rationality flag words in different languages (SI Appendix, section 9).

Various lines of evidence underpin the plausibility of an impact of social media on emotions, interests, and worldviews. For instance, there may be negative effects of the use of social media on subjective well-being (26). This can in part be related to distortions such as the perception that your friends are more successful, have more friends, and are happier (2728) and more beautiful (29) than you are. At the same time, a perception that problems abound may have been fed by activist groups seeking to muster support (30) and lifestyle movements seeking to inspire alternative choices (31). For instance, social media catalyzed the Arab Spring, among other things, by depicting atrocities of the regime (32), jihadist videos motivate terrorists by showing gruesome acts committed by US soldiers (33), and veganism is promoted by social media campaigns highlighting appalling animal welfare issues (31). Many of the problems highlighted on social media will be real, and they may have been hidden from the public eye in the past. However, independently of whether problems are exaggerated or merely revealed online, the popular effect of such awareness campaigns may be the perception of an unfair world entangled in a multiplicity of crises. Further down the gradient from revelation to exaggeration we find misinformation. The spread of misinformation (34) and conspiracy theories (35) may be amplified by social media, as the online diffusion of false news is significantly broader, faster, and deeper than that of true news and efforts to debunk (36). Conspiracy theories originate particularly in times of uncertainty and crisis (3537) and generally depict established institutions as hiding the truth and sustaining an unfair situation (38). As a result, they may find fertile grounds on social media platforms promulgating a sense of unfairness, subsequently feeding antisystem sentiments. Neither conspiracy theories nor the exaggerated visibility of the successful nor the overexposure of societal problems are new phenomena. However, social media may have boosted societal arousal and sentiment, potentially stimulating an antisystem backlash, including its perceived emphasis on rationality and institutions.

Importantly, the trend reversal we find has its origins decades before the rise of social media, suggesting that while social media may have been an amplifier other factors must have driven the stagnation of the long-term rise of rationality around 1975 to 1980 and triggered its reversal. Perhaps a feeling that the world is run in an unfair way started to emerge in the late 1970s when results of neoliberal policies became clear (2325) and became amplified with the rise of the internet and especially social media. A central role of discontent would be consistent with the rise in language characteristic of so-called cognitive distortions (39) known in psychology as overly negative attitudes toward oneself, the world, and the future (4043). If disillusion with “the system” is indeed the core driver, a loss of interest in the rationality that helped build and defend the system could perhaps be collateral damage.

Outlook

It seems unlikely that we will ever be able to accurately quantify the role of different mechanisms driving language change. However, the universal and robust shift that we observe does suggest a historical rearrangement of the balance between collectivism and individualism and—inextricably linked—between the rational and the emotional or framed otherwise. As the market for books, the content of the New York Times, and Google search queries must somehow reflect interest of the public, it seems plausible that the change we find is indeed linked to a change in interest, but does this indeed correspond to a profound change in attitudes and thinking? Clearly, the surge of post-truth discourse does suggest such a shift (4448), and our results are consistent with the interpretation that the post-truth phenomenon is linked to a historical seesaw in the balance between our two fundamental modes of thinking. If true, it may well be impossible to reverse the sea change we signal. Instead, societies may need to find a new balance, explicitly recognizing the importance of intuition and emotion, while at the same time making best use of the much needed power of rationality and science to deal with topics in their full complexity. Striking this balance right is urgent as rational, fact-based approaches may well be essential for maintaining functional democracies and addressing global challenges such as global warming, poverty, and the loss of nature.


Fig. 3. Ratio of intuition to rationality related words in the New York Times (A) and various book corpora represented in the Google n-gram database (BE). The graphs depict the ratio of the mean relative frequencies of the sets of rationality-related and intuition-related flag words presented in Fig. 1, right-hand columns.

Saturday, December 25, 2021

Participants overestimate the risks of nuclear accidents, except for disasters that should also trigger the behavioral immune system; & were more interested in reading/sharing a news article about a nuclear accident than about other types of accidents

Disgust sensitivity and public opinion on nuclear energy. Anne-Sophie Hacquin, Sacha Altay, Lene Aarøe, Hugo Mercier. Journal of Environmental Psychology, December 24 2021, 101749. https://doi.org/10.1016/j.jenvp.2021.101749

Highlights

• Participants overestimate the risks of nuclear accidents compared to other types of disasters.

• Participants were more interested in reading and sharing a news article about a nuclear accident than about other types of accidents.

• These two previous findings do not hold for for disasters that should also trigger the behavioral immune system.

• Participants were less willing to be in contact with an object that had been in a nuclear power plant than in a car manufacturing plant.

•  Arguments showing that nuclear power plants should not elicit fears of contamination reduced the negative perception of nuclear energy.

Abstract: An increasing number of experts agree that nuclear power should be part of the solution to fight climate change as it emits little greenhouse gases, has had no negative health consequences during normal operation, and even limited consequences after accidents. However, in many countries the population is much more ambivalent about nuclear power, and tends to exaggerate the negative effects on health and the environment. We suggest that this gap between experts and the public stems in part from nuclear power triggering the behavioral immune system: a set of cognitive adaptations that aim at protecting us against pathogens by making us particularly alert to their existence, and attuned to their risks. In line with this suggestion, we find that (i) participants overestimate the risks of nuclear accidents compared to other types of disasters (Experiment 1), except for disasters that should also trigger the behavioral immune system (Experiment 2); (ii) participants were more interested in reading and sharing a news article about a nuclear accident than about other types of accidents (with the same exception, Experiment 2); (iii) participants were less willing to be in contact with an object that had been in a nuclear power plant than in a car manufacturing plant (Experiment 3); (iv) arguments showing that nuclear power plants should not elicit fears of contamination reduced the negative perception of nuclear energy (Experiment 4). This work suggests a cognitive basis for the popular rejection of nuclear power, and ways to bridge the gap between experts and the public on this topic.

Keywords: Nuclear energyPublic opinionBehavioral immune systemRadiationFear of contaminationDisgust sensitivity


Friday, December 24, 2021

A number of popular research areas suggest that cognitive performance can be manipulated via relatively brief interventions; however, recent evidence indicates that cognitive abilities might not be as malleable as preliminary findings implied

Moreau, D. (2021). How malleable are cognitive abilities? A critical perspective on popular brief interventions. American Psychologist, Dec 2021. https://doi.org/10.1037/amp0000872

Abstract: A number of popular research areas suggest that cognitive performance can be manipulated via relatively brief interventions. These findings have generated a lot of traction, given their inherent appeal to individuals and society. However, recent evidence indicates that cognitive abilities might not be as malleable as preliminary findings implied and that other more stable factors play an important role. In this article, I provide a critical outlook on these trends of research, combining findings that have mainly remained segregated despite shared characteristics. Specifically, I suggest that the purported cognitive improvements elicited by many interventions are not reliable, and that their ecological validity remains limited. I conclude with a call for constructive skepticism when evaluating claims of generalized cognitive improvements following brief interventions. 


The golden ratio as an ecological affordance leading to aesthetic attractiveness

The golden ratio as an ecological affordance leading to aesthetic attractiveness. Daniela De Bartolo,Maria De Luca,Gabriella Antonucci,Stefan Schuster,Giovanni Morone,Stefano Paolucci,Marco Iosa. PsyCh Journal, December 23 2021. https://doi.org/10.1002/pchj.505

Abstract: The golden ratio (GR) is an irrational number (close to 1.618) that repeatedly occurs in nature as well as in masterpieces of art. The GR has been considered a proportion perfectly representing beauty since ancient times, and it was investigated in several scientific fields, but with conflicting results. This study aims at investigating if this proportion is associated with a judgment of beauty independently of the type of the stimulus, and the factors that may affect this aesthetic preference. In Experiment 1, an online psychophysical questionnaire was administered to 256 volunteers asked to choose among three possible proportions between the parts of the same stimulus (GR, 1.5, and 1.8). In Experiment 2, we recorded eye movements in 15 participants who had to express an aesthetic judgment on the same stimuli of Experiment 1. The results revealed a slight overall preference for GR (53%, p < .001), with higher preferences for stimuli representing humans, anthropomorphic sculptures, and paintings, regardless of the cultural level. In Experiment 2, a shorter dwell time was significantly associated with a better aesthetic judgment (p = .005), suggesting the possibility that GR could be associated with easier visual processing, and it could be hence considered as a visual affordance.

DISCUSSION

The main purpose of this study was to establish whether the presence of the GR may favor the perception of beauty in aesthetic judgments and which factors might influence it, clarifying the main controversies found in previous studies (Benjafield & Adams-Webber, 1976; Berlyne, 1970; Boselie, 1984; Davis & Jahnke, 1991; Di Dio et al., 2007; Fechner, 1865; Green, 1995; Witmer, 1893; Zeising, 1855).

First of all, we found a slight but significant preference for GR, but its entity depended on the category of the stimulus. This preference was statistically significant for human photographs, in both the experiments, and for sculptures and paintings in Experiment 1 (being only close to a significant threshold for virtual humanoid figures).

Conversely, we did not find a significant preference for GR in geometric stimuli. These findings are in line with some previous results (Di Dio et al., 2007; Di Dio et al., 2011) but in contrast with other studies finding a preference for GR also for geometric figures (Fechner, 1865; Russell, 2000). There are many possible explanations for the high variability among studies related to the possible preference for golden rectangles. First of all, it could be related to different methodologies related to how central tendency was computed: by means of mean, median, or modal values, with the GR that could emerge as mean value even if it was not the most frequent choice, as also previously suggested (Green, 1995). Indeed, in contrast to previous research on lines and geometric shapes' aesthetic preference, recent studies used more ecological experimental paradigms including natural and anthropomorphic figures, highlighting that geometric simple stimuli could be poorly attractive for our culture (Di Dio et al., 2007; Di Dio et al., 2011). Furthermore, with respect to the study of Fechner (1865) and successive ones, subjects are now more often exposed to rectangular shapes different from GR, such as those of television screens, monitors, or smartphones having proportions closer to 1.8 (16:9 = 1.78, or 1980:1020 pixels = 1.78), or also paper sheets closer to 1.5 (A4: 1.41).

The GR is often present in many natural stimuli (Iosa et al., 2018). Indeed, subjects might prefer stimuli recognized as original, as in our study occurred for human photographs, with GR preferred for stimuli originally in GR (oGR vs. noGR), despite participants not knowing which was the original stimuli.

The golden section was conceivably identified by anatomical Greek investigations in the 5th century BCE (as in the canon of Protagoras) with the idea to reproduce the harmony of the human body in the anthropomorphic sculptures and then in other artworks (Haines & Davies, 1904; Iosa et al., 2018). It should be considered that anthropomorphic stimuli have their own symmetry given by the right–left relationship along the horizontal axis, whereas the golden section defines the vertical harmony of a standing human being. Hence, the GR preference could occur more frequently on the vertical than horizontal axis. Despite our studies not investigating this aspect, it should be noted that the rectangles of Fechner (1890) had the longer segment along the vertical axis, whereas in our and other studies (McManus, 1980; Russell, 2000) the longer dimension of rectangles and that of the bisected line was the horizontal one.

Despite this, Renaissance artists provided a horizontal division of their paintings according to the golden section, such as in The Flagellation of Christ and The Creation of Adam (de Campos et al., 2015), with these stimuli that can be mentally divided into two parts and visually explored horizontally. A slight preference for GR was found in our paintings (54.6%), quite independent if the original stimuli was or not in golden proportion. Wölfflin (1994) questioned the preference for GR when observing an abstract rectangle because it should be related to a mental comparison of the lengths of basis, height, and their sum, again claiming that GR may “present an average measure conforming to man”.

This hypothesis put in relationship the GR with “objective beauty”, because it was related to a harmonic property intrinsic to the stimuli, but there is also an alternative hypothesis, reported in the so-called constructal theory, referring to “perceptual beauty” suggesting that the preference for GR was related to the hypothesis that visual system scans the world approximatively in golden proportion (Bejan, 2009). Di Dio et al. (2007) identified also the “subjective beauty” driven by one's own emotional experiences and related to the activation of the amygdala, whereas the objective beauty related to the intrinsic properties of the stimulus is based on a joint activation of sets of cortical neurons of lateral occipital cortex, parietal cortex, and anterior insula. All these processes could be not mutually exclusive and cohabit, forming our sense of beauty.

This integrated approach works even better considering GR as an affordance, and hence a property intrinsic to the stimulus that is recognized by our visual system and favoring the visual process. In fact, Gibson proposed the theory of affordances, suggesting that subjects noted the features of a stimulus that may constitute functional relations between the stimulus and the perceiver (Gibson, 2014; Lobo et al., 2018). The abstraction of geometric figures and even of virtual humanoids might hence have mitigated this preference, in accordance with the ecological approach suggested by Gibson for the visual system (Gibson, 2014). The cultural level of subjects did not seem to influence the general preference for GR. This result could be read in conjunction with previous findings that the aesthetic judgment of beauty was mainly independent by sociocultural factors, intelligence, personality, and age (Eysenck & Tunstall, 1968). However, in our study, culture was assessed in terms of scholarly level, but different cultures were not analyzed, and further studies could investigate the preferences for GR comparing subjects of Western versus Eastern Countries.

When we analyzed single categories of stimuli, the preference for GR in human photographs and sculptures was related to art knowledge. These two types of stimuli have in common the same criterion for GR: the ratio between the distance of the navel from the ground and that between the navel and the top of the head. Virtual humanoids had the same proportion, but the judgments about them seemed to be not affected by cultural level. Probably, this judgment mainly depended on the realism of their faces, as shown by the long time spent by observers looking at the virtual faces in Experiment 2. Furthermore, being human bodies on average in GR, humans might have reflected this proportion in the concept of beauty, and it led to the adoption of this parameter also in some classical artistic masterpieces, starting from anthropomorphic sculptures (Hernández-Castro, 2007).

Human beings may associate, more or less consciously, the concept of beauty to their own body proportions (Burrell, 1932), as is the case with the preference of symmetric figures that could be related to the symmetry of the human body (Evans et al., 2012; Huang et al., 2018; Mühlenbeck et al., 2016). As well as symmetry being considered as an affordance in accordance with the ecological approach suggested by Gibson for vision (2014), the GR that can be considered as a symmetry of higher order (Liu & Sumpter, 2018) could also be another visual natural affordance, preferred by humans and put in artworks by artists.

In our study, the proposed paintings have the longest dimension horizontal; indeed, the golden ideal division was along the horizontal axis. A slight preference (54.6%) was found for GR, quite independently if the stimulus was or not originally in GR. With respect to the geometric figures, participants could perceive the harmony of a scene ideally divided in two parts according to the GR, even if this scene is represented with the horizontal length longer than the vertical. Considering that for symmetry there is a perceptual sensitivity to the orientation of the stimulus (1905; Fisher & Bornstein, 1982; Mach, 1883), and that there are no studies that directly investigated the relationship between GR and the orientation of the stimulus, future studies should investigate whether there is a dependence on the orientation with which it is presented the stimuli and the possible preference for GR.

Despite our study lacking this direct comparison, the bimodal distribution of dwell time found in Experiment 2 for human figures for which the golden section regards the vertical axis, are similarly replicated for the paintings in which it regards the horizontal axis. In general, the results of Experiment 2 were found in accordance with those of Experiment 1 and seem to confirm the hypothesis of GR as an affordance. In Experiment 2, we found no significant differences between the three proportions related to the total exploration time, but also some significant differences with respect to specific areas of interest. Further, analyzing the dwell times, significant differences among GR, R1.5, and R1.8 were found regarding the exploration of the AOIm, that is, the specific AOI where the image modification was performed. A significant negative correlation was found between the AOIm dwell time and the aesthetic judgment only for GR stimuli. This could indicate that the subject does not need to observe that area for too long to judge it as beautiful if it is in golden proportion.

Despite previous studies showing that the aesthetic appreciation of beauty is not based on an “immediate” response and may even require more time to discriminate the main characteristics of the stimuli (Bar et al., 2006; Evans et al., 2012; Huang et al., 2018; Liu & Sumpter, 2018; Mühlenbeck et al., 2016), the presence of GR may have reduced this time because it was quickly recognized and preferred by the observers. So, hypothesizing GR as an affordance, it may be implicitly recognized, facilitating the processing of visual information relating to a stimulus, making aesthetic experience more fluent, in accordance with the “processing fluency theory” for which that fluency could contribute to the pleasantness of the experience associated with the perception of beauty (Witmer, 1893).

It is noteworthy that the GR divides the human stature in a region roughly close to the body center of mass and could even play an important role in human motor behavior (Iosa et al., 2018). It should be noted that the exposition to GR does not regard only the visual system: GR was recently found as a harmonic feature of voluntary and involuntary rhythmic human movements, such as cardiac (Yetkin et al., 2013), respiratory (Iared et al., 2016), and walking rhythms (Iosa et al., 2013; Iosa et al., 2016; Iosa et al., 2019; Serrao et al., 2017). In fact, walking performed with GR between gait phases allows humans to harmonize locomotor acts (Iosa et al., 2016; Iosa et al., 2019), thus reducing energy expenditure (Serrao et al., 2017). Furthermore, it has been demonstrated that perception of internal gait rhythm may be modulated (De Bartolo, Belluscio, et al., 2020a) and that the harmonic structure of music can ameliorate harmony of walking in patients with Parkinson's disease (De Bartolo, Morone, et al., 2020b), especially if acoustic stimulation presents GR harmony (Belluscio et al., 2021), confirming the possibility to consider GR as an affordance to exploit by the observer/listener/acting subject.

However, we must bracket this proposal with some caveats. The main limitation of Experiment 1 was the online administration of the questionnaire that did not allow for controlling some variables such as the eyes' positions with respect to the screen, the response time of the subjects, or their attention level. For example, the questionnaire was formed by 51 items, and it might have led to a progressive physiological decline in the participants' attention due to fatigue.

However, the online administration allowed for enrolling a wide sample of subjects (N = 256) that could have attenuated the above-mentioned limits. Experiment 2 was performed in more controlled conditions, and its results confirmed those obtained in Experiment 1. Subjects were required to judge the most liked stimulus, without any investigations related to the judgment of naturalness, so caution is needed in discussing the role of naturalness of stimuli and its relationship to the preference for stimuli originally or not in GR.

Finally, in our study we did not manipulate canonical orientation of stimuli, so we included only vertical stimuli for anthropomorphic figures and horizontal for images of artworks. Further studies should investigate the possible differences in the GR preferences for vertical versus horizontal stimuli, and these results could contribute to understand the relationship between GR and visual scan process.

An Eye-Tracking Investigation on Mirror Gazing: Those of higher self-esteem spent less time checking themselves in a mirror

Effects of Self-Esteem on Self-Viewing: An Eye-Tracking Investigation on Mirror Gazing. Jonas Potthoff, Anne Schienle. Behav. Sci. 2021, 11(12), 164. Nov 29 2021. https://doi.org/10.3390/bs11120164

Abstract: While some people enjoy looking at their faces in the mirror, others experience emotional distress. Despite these individual differences concerning self-viewing in the mirror, systematic investigations on this topic have not been conducted so far. The present eye-tracking study examined whether personality traits (self-esteem, narcissism propensity, self-disgust) are associated with gaze behavior (gaze duration, fixation count) during free mirror viewing of one’s face. Sixty-eight adults (mean age = 23.5 years; 39 females, 29 males) viewed their faces in the mirror and watched a video of an unknown person matched for gender and age (control condition) for 90 s each. The computed regression analysis showed that higher self-esteem was associated with a shorter gaze duration for both self-face and other-face. This effect may reflect a less critical evaluation of the faces.

Keywords: face; self-perception; mirror; eye-tracking; self-esteem; self-disgust; narcissism

4. Discussion

This study investigated whether gaze parameters while viewing one’s face in the mirror are associated with the personality traits of self-esteem, self-disgust, and narcissism propensity. High self-esteem indicates that, on the whole, individuals are satisfied with themselves and are not overly critical [30,31]. In previous eye-tracking research, elevated self-esteem was associated with attentional biases towards self-faces [13]. Surprisingly, in the present investigation, higher self-esteem was associated with shorter—possibly less critical—viewing of the own face. It is possible that people with high self-esteem need less time to evaluate themselves (critically), while low self-esteem seems to be associated with a more thorough and more prolonged evaluation of one’s facial appearance.
Following this interpretation, the shorter viewing time of the other face associated with higher self-esteem would imply that individuals with high self-esteem are also less critical of others [32]. It is possible that in previous research [13] this viewing pattern could not be identified due to brief exposure times. The participants looked at the faces until they identified them. This took them less than one second on average. Additionally, in previous research, faces were not viewed freely, and task demands (face identification) may have overruled a critical and thorough evaluation of the faces [13]. Future research needs to investigate the effect of exposure time and viewing tasks on gaze behavior concerning self-face and other-face.
Self-esteem did neither predict the number of fixations on self-face nor other-face. Many short fixations (i.e., hyperscanning) are commonly conducted when affective stimuli with negative valence and high intensity are explored [22,33]. In the present study, dynamic faces with neutral expressions were viewed, which do not induce high arousal, at least in non-clinical samples [19,20,21]. While self-esteem predicted a more thorough evaluation of faces (longer viewing time), it was not associated with visual hyperscanning, which would have required elevated arousal. Taken together, the results suggest that low self-esteem is related to a thorough but calm evaluation of faces.
Earlier investigations indicated that the number of fixations on specific face areas differs between self-face and other-face viewing. Hoffmann et al. [8] observed that more fixations were conducted on the eyes when viewing unfamiliar faces than the own face. We refrained from using a similar analysis approach (an analysis of fixation counts for specific facial areas) because of insufficient spatial precision of the measuring procedure. There are slight interindividual differences in the position of facial features (e.g., location of eyes, mouth), which cannot be detected with sufficient spatial accuracy during mirror viewing. It would have been possible to control for the location of the eyes during mirror viewing by adjusting the chinrest for each participant until they see their eyes at a predefined mirror location. This procedure would, however, lead to self-face exposure before the eye-tracking experiment begins. Therefore, we focused on the gaze behavior for the face as a whole.
There was no relationship between NPI scores and gaze behavior. Narcissism propensity was neither associated with a more thorough (prolonged) viewing nor hyperscanning. These null-findings contrast our expectations and previous research, especially for self-face viewing [15]. In the present paradigm, participants viewed self-faces and other faces one after another and not simultaneously (e.g., as image pairs). It is possible that associations between narcissism propensity and viewing behavior did not show up because participants could not directly compare their faces with the faces of others. Furthermore, participants did not perform any task in which they could have compared their performance with the performance of others. Future studies should investigate whether narcissism propensity is associated with specific self-face viewing behaviors in competitive contexts (i.e., when comparing one’s own and others’ physical appearance).
The NPI assesses feelings of self-importance. However, narcissism has different facets. It has been suggested to distinguish between grandiose and vulnerable narcissism [34,35]. Vulnerable narcissistic individuals are anxious, defensive, and avoidant, while grandiose narcists are extraverted and self-satisfied [36]. Additionally, there are intrapersonal and interpersonal aspects of narcissism [37]. To maintain a grandiose self, people with a high narcissism propensity might, on the one hand, strive for feelings of uniqueness (intrapersonal) [38]. On the other hand, they can also devaluate others or strive for supremacy (interpersonal) [39]. Therefore, more differentiated NP measures should be used in the future, which can differentiate between these separable yet related expressions of narcissism that should prompt different styles of self-viewing [40].
Self-disgust also showed no association with viewing the own face. Self-disgust has been conceptualized as a dysfunctional personality trait [12,41] which typically has a very low level in mentally healthy individuals [41]. This was also the case in the present investigation. In contrast, Ypsilanti, Robson et al. [6] analyzed eye-tracking data from participants with mental health problems. This group with elevated self-disgust displayed avoidance of self-viewing. Therefore, the present null results do not contrast previous findings [5,6]. Future research should further investigate self-face viewing in conditions with elevated self-disgust, such as depression [2,42], disordered eating [43,44,45], and body dissatisfaction [45,46,47]. For example, body dysmorphic disorder (BDD) is associated with high self-disgust [47] but not with avoidance of self-viewing. Many patients with BDD even report spending a significant amount of time checking themselves in the mirror [45]. Mirror viewing paradigms can therefore contribute to a deeper understanding of self-viewing avoidance as well as excessive mirror viewing in eating disorders and BDD. For these disorders, mirror exposure is a commonly used therapy component [48].
We also investigated possible gender effects on face-viewing behavior. In general, males, as well as females, spent the majority of the 90 s-viewing time on the faces. Thus, there was no indication of face avoidance. Male participants were characterized by a longer total viewing time. They showed a longer gaze duration for both the own face and the other face. Previous studies have already demonstrated that face exploration dynamics (for other faces) differentiate men and women [49,50]. In an investigation by Coutrot et al. [49], the participants (203 males and 202 females) watched videos of actors. Male participants showed longer fixation durations for the faces than female participants. However, this difference was small. Overall, face viewing has many functions and serves multiple purposes (e.g., aiding speech perception [51], emotion recognition [52], person identification [53], or affective evaluation [15]). Moreover, context factors (e.g., cultural, social) have to be considered as well [54]. It needs further investigation whether differences in face-viewing intentions might have contributed to the observed gender difference in gaze duration.
It is plausible that several limitations might have influenced the results obtained. We studied a convenience sample, and the participants were healthy, predominantly young students. Therefore, the present results cannot be generalized to other samples. Furthermore, the study did not differentiate between different aspects of narcissism propensity.