Monday, February 17, 2020

Sex declines, but engagement in, or being target of, dominant behaviors (spanking, choking, name calling, performing aggressive fellatio, facial ejaculation, penetration without first asking/discussing) seems more frequent

Sex frequency and satisfaction seems to be declining in the West:
Declining Sexual Activity and Desire in Women: Findings from Representative German Surveys 2005 and 2016. Juliane Burghardt et al. Archives of Sexual Behavior, December 4 2019. https://www.bipartisanalliance.com/2019/12/declining-sexual-activity-and-desire-in.html
How strong the tendency among Finns still is to form only one, life-long relationship? Changes in how many partners they have, same-sex experiences, masturbation, etc. Monogamy vs Polygamy. Osmo Kontula. SexuS Journal, Winter-2019, Volume 04, Issue 11, Pages 959-978. https://www.bipartisanalliance.com/2019/09/kow-strong-tendency-among-finns-still.html


, but roughness seems to be increasing:

Herbenick D, Fu T-C, Wright P, et al. Diverse Sexual Behaviors and Pornography Use: Findings From a Nationally Representative Probability Survey of Americans Aged 14 to 60 Years. J Sex Med 2020;XX:XXX–XXX, Feb17 2020. https://doi.org/10.1016/j.jsxm.2020.01.013

Abstract
Background  Convenience sample data indicate that substantial portions of adults have engaged in sexual behaviors sometimes described as rough; little is known about these behaviors at the population level.

Aim  To describe, in a U.S. probability sample of Americans aged 18 to 60 years, (i) the prevalence of diverse sexual behaviors, described here as dominant and target behaviors; (ii) the age at first pornography exposure as well as prevalence, range, and frequency of pornography use; (iii) the association between past year pornography use frequency and dominant/target sexual behaviors; and (iv) associations between lifetime range of pornography use and dominant/target sexual behaviors.

Methods  A confidential cross-sectional online survey was used in this study.

Outcomes  Lifetime engagement in dominant behaviors (eg, spanking, choking, name calling, performing aggressive fellatio, facial ejaculation, penile-anal penetration without first asking/discussing) and lifetime engagement in target behaviors (eg, being spanked, being choked, being called names during sex, having their face ejaculated on, receiving aggressive fellatio, or receiving penile-anal penetration without having discussed) were assessed; lifetime pornography use, age at first porn exposure, past-year frequency of porn viewing, and lifetime range of pornography were also assessed.

Results  Women as well as men who have sex with men were more likely to report target sexual behaviors: having been choked (21.4% women), having one's face ejaculated on (32.3% women, 52.7% men who have sex with men), and aggressive fellatio (34.0% women). Lifetime pornography use was reported by most respondents. After adjusting for age, age at first porn exposure, and current relationship status, the associations between pornography use and sexual behaviors was statistically significant.

Clinical Implications  Clinicians need to be aware of recent potential shifts in sexual behaviors, particularly those such as choking that may lead to harm.

Strengths & Limitations  Strengths include U.S. probability sampling to provide population level estimates and the use of Internet-based data collection on sensitive topics. We were limited by a lack of detail and context related to understanding the diverse sexual behaviors assessed.

Conclusion  Clinicians, educators, and researchers have unique and important roles to play in continued understanding of these sexual behaviors in the contemporary United States.

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Check also previous work by some of these authors:

Feeling Scared During Sex: Findings From a U.S. Probability Sample of Women and Men Ages 14 to 60. Debby Herbenick, Elizabeth Bartelt, Tsung-Chieh (Jane) Fu, Bryant Paul, Ronna Gradus, Jill Bauer et al. Journal of Sex & Marital Therapy , Volume 45, 2019 - Issue 5, Pages 424-439, Apr 4 2019. https://doi.org/10.1080/0092623X.2018.1549634

Abstract: Using data from a U.S. probability survey of individuals aged 14 to 60, we aimed (1) to assess the proportion of respondents who ever reported scary sexual situations and (2) to examine descriptions of sexual experiences reported as scary. Data were cross-sectional and collected via the GfK KnowledgePanel®. Scary sexual situations were reported by 23.9% of adult women, 10.3% of adult men, 12.5% of adolescent women, and 3.8% of adolescent men who had ever engaged in oral, vaginal, or anal sex. Themes included sexual assault/rape, incest, being held down, anal sex, choking, threats, multiple people, novelty/learning, among others.

Discussion

Our study provides insights into sexual experiences that 14- to 60-year-old Americans have found scary. Rather than investigate a specific behavioral category (e.g., sexual assault or coercion), we chose to center on respondents’ emotional lives and ask about scary experiences. We hoped to understand more about sexual events that may be problematic, hurtful, or frightening and that may otherwise be missed in research focused only on sexual violence. Our research questions were informed by having heard from students and interview participants, over a number of years, about frightening sexual experiences that seemed to go beyond “bad hook-ups” (Littleton, Tabernik, Canales, & Backstrom, 2009). Sometimes people would describe sexual encounters that were frightening in their entirety; other times, the frightening experience occurred within an otherwise pleasurable sexual encounter. We aimed to augment the literature by addressing both the prevalence of scary sexual experiences and respondents’ descriptions of these.

We were struck, but not surprised, at the gendered aspects of our findings. Substantially more women than men reported that someone had done something during sex that had scared them. This is likely because scary things truly do happen more often to women than men during sex. This is important considering that women’s allegations of assault are still sometimes characterized as simple “misunderstandings” (e.g., Kitchener, 2018; Levin, 2016). We note that some of the men’s descriptions of scary sex (e.g., that referred to menstruation, adolescent/learning curve, first coitus, wondering whether the person who’s performing oral sex is friends with a prior partner) differed considerably from examples more often provided by women that pertained to rape, forced sex, being held down, threatened with weapons, choked, and painful sex that one asks to stop but that does not stop. Even among the pregnancy/STI risk responses, women’s experiences more often alluded to feeling pressured into unprotected sex. In contrast, men’s responses in this category described forgetting to use a condom, not knowing about a partner’s sexual history, or finding out a female partner had many prior sex partners. And yet, the overall proportion of men who reported ever experiencing sex as scary was nearly half that of women; subsequent research might focus on better understanding the range of (perhaps underreported) male trauma.

We identify these gendered differences not to dismiss the experiences of men who had sex with women and who felt scared about some aspect of sex, but to highlight the different kinds of sex (and perhaps the different kinds of fear) that people grapple with during their sexual exploration and development. Those who have not generally experienced alarming aspects of sex, moments in which they wondered whether they were about to be raped or killed, may find it difficult to imagine how scary sex can feel for others. Consequently, some may find it difficult to empathize with what it means to be a sexually active woman in a society where quite scary things happen; we are reminded of Gavey (2012), who wrote about “sexuality in a sexist world.”

We note, too, that quite a few of the men who described scary sexual situations (especially those that involved physical aggression or forced penetration) alluded to the other person being male. This finding is consistent with literature demonstrating that gay and bisexual men are at disproportionately greater risk of sexual violence (Rothman, Exner, & Baughman, 2011). That adults who report lower household income were more likely to report having had scary sexual experiences should be further interrogated. It may be that the scary experiences were traumatic in ways that altered life and career paths for some individuals. Others may have experienced scary sexual experiences as part of a larger pattern of disadvantage or differential opportunity or may have put up with sexual coercion because they felt they had limited options.

We were struck by how often the scary experiences reflected interpersonal violations of the sexual rights identified by WAS (World Association for Sexual Health, 2014). For example, those who wrote about their partner continuing sex after being asked to stop experienced a violation of their autonomy. Respondents who wrote about forced sex, sexual assault, or rape experienced a violation of their right to be free from sexual violence and coercion. In addition, those whose request to use contraception was ignored experienced violations of rights related to making their own reproductive choices. Because the scary experiences were also disproportionately reported by women as well as by men who have sex with men, collectively they reflect sexual inequities derived from societal inequities. Sex that disproportionately frightens women and other minoritized individuals reflects cultural and social issues that need to be reckoned with.

Our findings add to a body of literature that, as described earlier, demonstrates a privileging of men’s sexual pleasure, with women more often reporting lower levels of sexual pleasure and arousal, less frequent orgasm (Herbenick et al., 2010b), more frequent pain (Herbenick et al., 2015) and, described here, more common experiences of frightening sex. Indeed, scholars have long described how women’s economic and political insubordination impacts their sexual lives and opportunities (e.g., Tiefer, 2001), making them vulnerable to sex that feels scary, painful, or beyond one’s ability to control or consent to (e.g., Bay-Cheng, 2010; Gavey, 2012; Tiefer, 2001).

Even in consensual sex, women more often give reasons for having sex that include feeling pressured, obligated, or at the insistence of one’s partner (Meston & Buss, 2007). In addition, many young women choose to continue having vaginal intercourse even when it is painful, not wanting to spoil sex for their partner by interrupting sex (Elmerstig, Wijma, & Swahnberg, 2013). What we know less of is how this comes to be. How common is it for women to begin their sexual lives believing that sex should continue at all costs, even if it hurts? Alternatively, is this something that some women learn from trying to stop painful intercourse only to have their partner ignore their request?

Aside from sexual assault and rape, some of the most common descriptions of sexual situations that respondents found scary involved anal sex or choking. Indeed, in the past few decades, the prevalence of Americans reporting lifetime anal sex has nearly doubled, even as the frequency has remained low (Herbenick et al., 2010a). For such a common behavior, we found it striking how commonly anal sex was included in descriptions of scary sex. Subsequent research might further explore this. To what extent is anal sex scary at first but then evolves into a neutral or even pleasurable experience? What do individuals find scary about anal sex? For some respondents, it seems that the scary aspect was that they had already communicated to their partner that they did not want to have anal sex, but their partner coerced or forced anal sex anyway. For others, their partner did not stop after they were asked to stop or else anal sex got too rough, suggesting that anal sex itself might not necessarily have been scary had it been wanted, consensual, and better communicated about. (By “communicated” we acknowledge the critical roles of both verbal communication and listening/responding.) Indeed, in a series of studies of college men and women, it was not uncommon for women to indicate that their refusals to engage in various sexual behaviors were often met with men expressing displeasure, anger, or continuing with sexual advances despite the woman’s expressed wishes to stop (see Byers, 1996, for overview).

Choking and other aggressive behaviors (such as hitting and forceful hair pulling) were also often described among the scary sexual experiences. Like anal sex, choking appears to have become more commonly portrayed in sexually explicit media and sexual choking behaviors (and interest in choking) are associated with pornography use (Bridges, Sun, Ezzell, & Johnson, 2016; Sun, Wright, & Steffen, 2017). In recent years, choking and various forms of breath restriction/breath play have also become a part of nonsexual games that some adolescents engage in (Linkletter, Gordon, & Dooley, 2010). However, choking and breath play are associated with serious risks—including accidental death—and thus it is not surprising to see choking often described as scary. Most of the choking instances described appear to have not been discussed by partners in advance; the other person just started choking the respondent. Consequently, some worried they were being strangled: a common form of intimate partner violence, especially committed against women who partner with men (Messing, Thomas, Ward-Lasher, & Brewer, 2018). Given how little is known about the role of choking in contemporary sexual repertoires, we encourage subsequent research to consider questions such as the following: How do people first learn about choking during sex? To what extent are sexually explicit media contributing to sexual behaviors such as choking? What do they learn about it? What kinds of conversations do sexual partners have about choking?

Our data provide opportunities for sexuality therapists, educators, parents, and couples to think about the many different ways that sexuality can be experienced. Findings underscore that unwanted, unpleasurable, and even frightening things can happen during sex that is otherwise wanted and pleasurable. Even well-meaning partners can err by introducing sex toys or sex acts that the other person does not like. Our data also speak to the importance of listening to one’s sex partner, that is, not doing something that they have said they do not want to do, stopping sex when they ask to stop, and using condoms or other contraceptives if they ask to do so. Clinicians have a critical role to play in supporting clients to create consensual and mutually pleasurable sexual lives. Clinicians might also consider asking clients about their past experiences with scary or frightening sexual experiences, as sexual history guides often address assault or rape but few other kinds of negative situations.

Strengths and limitations

A strength of our study is that we used the GfK KnowledgePanel, which uses probability-based sampling for panel establishment and is intended to be nationally representative of the English-speaking, non-institutionalized U.S. population. This method was well suited to establishing the prevalence of having experienced scary sexual situations among the U.S. population. We took care to communicate to parents the aims of our study and how we would go about showing questions to their adolescent sons and daughters that were appropriate for their sexual development and experiences to date. Yet, it is possible that parents chose not to allow us to survey their child if they felt their son or daughter was sexually naïve or if they knew they had experienced sexual trauma. As with any study, we can imagine varied reasons that some people may choose not to participate in a study or to allow their child to do so. Given the small number of adolescent reports, these estimates should be viewed with caution and subsequent research should examine adolescents’ scary sexual experiences in greater detail. We also have no way of knowing the full range of scary experiences that respondents had actually endured, and some respondents may have chosen to share a relatively neutral example rather than share something particularly frightening to them. Conversely, some respondents may have chosen to share the worst or more frightening example.

We also collected data over the Internet, which has been shown to facilitate reporting on sensitive topics (Burkill et al., 2016). Yet, a limitation of Internet-based surveys is that they tend to yield less detail than do in-person interviews (some people declined to provide examples of scary situations and others wrote only brief responses). Subsequent research might utilize interviews to better understand the details of individuals’ scary sexual experiences. For this initial study, we were content to leave the idea of feeling “scared” open to interpretation so that we could understand a range of experiences. However, subsequent research may want to differentiate feeling scared about one’s safety versus scared about novel experiences.

Due to budget-related survey space restrictions, we only asked two questions about scary sexual experiences. We did not ask about respondents’ age at the time of the experience, the gender(s) of those involved, or other details. It is unclear how recall bias may have factored into respondents’ endorsement of having experienced scary sexual situations. We hope that our study, in presenting sexual situations experienced as scary, may inform the development of more nuanced research going forward. Subsequent research might investigate how scary situations are resolved (if/when they are) and how they become incorporated into individuals’ sexual learning (e.g., what changes, if any, people make in their lives following scary experiences). Researchers might also examine how people interpret scary sexual situations (including how they may be recast over time), including the extent to which they feel guilt, shame, or anger or alternatively minimize their experience, as commonly occurs in sexually coercive situations (Jeffrey & Barata, 2017).

Our study is not able to address the prevalence of particular types of scary sex. For example, we cannot speculate what percentage of Americans have experienced choking and felt scared by it. Respondents could provide any example of a scary sexual experience, which may have been one of their more frightening or one markedly less so. Our data might inform the development of future checklists of potentially scary situations. The use of such a checklist would be better able to address population-based prevalence of specific experiences.


Children's understanding of dominance and prestige in China and the UK

Children's understanding of dominance and prestige in China and the UK. Anni Kajanus, Narges Afshordi, Felix Warneken. Evolution and Human Behavior, Volume 41, Issue 1, January 2020, Pages 23-34. https://doi.org/10.1016/j.evolhumbehav.2019.08.002

Abstract: Individuals can gain high social rank through dominance (based on coercion and fear) and prestige (based on merit and admiration). We conducted a cross-cultural developmental study and tested 5- to 12-year-olds, and adults in the UK and China, aiming to determine (a) the age at which children distinguish dominance and prestige, and (b) the influence of cultural values on rank-related reasoning. We specifically tested participants in China because of the value of prestigious individuals modestly yielding to subordinates, a social skill that becomes more salient with age. In both populations, the distinction between dominance and prestige emerged at five years, and improved over childhood. When reasoning about a resource conflict between a high-ranking party and a subordinate, adults in both countries expected high-rank individuals to win, although Chinese adults were less likely to do so regarding prestigious individuals. Across the two countries, younger children (5–7 years) responded similarly to each other, not favoring either party as the winner. Older children (9–12 years), however, diverged. Those in the UK chose the high-rank party, while those in China made no systematic inference. Overall, our findings suggest that while children distinguish prestige and dominance comparably in the two countries, they develop culturally-influenced expectations about the behavior of high-rank individuals.

5. General discussion

Our aims were to test: (1) the age at which children differentiate dominance and prestige; and (2) the influence of cultural ideas of hierarchy and conflict on expectations about the behaviors of dominant and prestigious individuals. The experiments yielded several key findings for both lines of inquiry.
 
(1)  Developmental trajectory
First, 5- to 12-year-olds in both the UK and China easily identified dominant and prestigious characters as high-ranking. Thus, even for the younger group of children (5–7 years), cues to prestige (e.g. asking for advice, following said advice) were enough to merit inferences about rank. In fact, children were just as successful at recognizing that the prestigious character was higher-ranking as they were for the dominant character. Next, even younger children distinguished between prestigious and dominant characters in a third-party situation, choosing the prestigious character significantly more when asked whom the subordinate would approach or like, than when asked whom she feared. This finding is particularly interesting in light of the fact that children do not shun coercive (or dominance-like) strategies in their peer groups until eight years (Hawley, 1999). Since our younger group was younger than eight years, the finding suggests that shunning coercive strategies is not the result of noticing the difference between dominant and prestigious strategies. Nonetheless, the ability to distinguish dominance and prestige improved with age. Finally, there were no differences between responses in the UK and China, providing some of the first empirical evidence of children from non-Euro-American cultures understanding cues to rank similarly to children in Europe and the US. In summary, children attributed a combination of traits to the characters that are reflective of a conceptual distinction between dominance and prestige, viewing both as having high social rank, but differing in prestigious characters being liked and approached versus dominant individuals being feared and avoided.
One alternative explanation of the findings from Experiment 1 is that children did not actually distinguish dominance from prestige, and instead succeeded in the task by answering the questions (age, liking, approach, fear) piecemeal. In other words, maybe they answered that Dimo would like and approach the prestigious character simply because the character seemed nice and friendly, and feared and avoided the dominant character because that one seemed mean and aggressive. Similarly, children could have inferred age (i.e. rank) by drawing on cues like being imitated. We do not dispute that these cues led children to answer the questions correctly. In fact, we claim that this is exactly what the understanding of prestige and dominance looks like: an understanding of this combination of features. None of these individual features differentiates between dominance and prestige, but one person having high status while being nice and approachable differentiates this person from a similarly high-ranking individual who is mean and aggressive.
Although younger children recognized the rank difference between the characters just as easily as older children (Experiment 1), they did not infer that higher-ranking parties would win resource conflicts (Experiment 3). This failure cannot be attributed to a cultural effect, as children in the UK and China performed similarly. When asked to justify their choice of who would win the conflict, almost no children referenced rank in their explanations, confirming that their failure to infer is a real consequence of how they construed the scene. Thus, although younger children extracted rank from watching interactions between characters in Experiment 1, they were unable to automatically incorporate them into inferences about subsequent behaviors in Experiment 3. Future work should explore this finding further.
 
 
(2)  Cross-cultural differences
A key contribution from our studies is evidence for the influence of cultural norms and value systems on how children and adults understand social hierarchies and reason about them. Adults in the UK and China were similar in that they both inferred that high-ranking characters would win against a subordinate. They did differ, however, in the degree to which they made this inference in the prestige case. Chinese adults were less likely than British adults to think that the prestigious person would win the resource. This difference, while subtle, is a key sign of the cultural difference reflecting the value specifically placed on yielding to others when in a position of prestige (Kajanus, n.d.). The cultural difference also manifested in older children (9–12 years), but in a different way. Older children in the UK inferred that the high-ranking party would win the conflict, regardless of whether the character was prestigious or dominant. In contrast, older children in China responded similarly to younger children in both countries, demonstrating no systematic prediction about who would win in either of the conflict cases. But unlike younger children's explanations, which were shallow and unrelated to social rank, older children in China and the UK provided similar levels of rank-relevant explanations (around 65%). Consequently, the lack of systematic inferences was age-driven in younger children, but culturally influenced in older children in China. Moreover, older children in China who thought the subordinate would win the conflict were more likely to mention the prestigious character yielding than the dominant character yielding. This finding aligns with the value of yielding by prestigious individuals. Together, these findings suggest that the difference between older children in China and the UK is rooted in a cultural difference.
On the topic of Chinese participants' choices, two points merit further discussion. With regard to adults, the fact that Chinese participants thought that both dominant and prestigious parties would win the conflict gives room for pause, given the value of prestigious individuals showing restraint and giving up resources to lower-status parties. However, it is important to note that yielding to those in lower positions is a sophisticated social skill highly dependent on the nuances of the situation, such as the dynamics of ascribed status hierarchies and the importance of the issue at the root of the conflict (Kajanus, n.d.). Thus, most adults may have viewed the situation as one in which the high-ranking character lacked the sophistication to yield, given the cartoonish appearance of the characters, the simplicity of the exchanges, and the prestigious character's unabashed and juvenile desire for the resource. This may have made the high-ranking character's win the more straightforward choice. A number of them may have, nonetheless, considered the situation in terms of the prestigious character yielding, thereby bringing about the difference with the British adults.
Another puzzling finding has to do with the older Chinese children's responses in Experiment 3. In a reverse situation from the adults, children held no expectation of either party winning in either conflict case. The lack of a clear prediction may be understandable for the prestige case, but is more surprising in the dominance case. As the data do not clarify the reason for this result, we can only speculate. One likely account is that children at this age are not yet fully proficient in the complexities of rank relations and the rules of yielding. They have learned that high-ranking persons will sometimes yield, but the ways in which personality characteristics (e.g. prestige, dominance) and ascribed hierarchies (position, age, gender, etc.) factor into yielding are still unclear. It is therefore possible that even though they distinguish between dominant and prestigious processes, in relation to yielding they simply treat them similarly as signs of high rank. It is notable that even adults of both countries treated the prestige and dominance cases the same in their predictions about yielding. This does not mean that they cannot distinguish between prestige and dominance as bases of high rank. Unlike Experiment 1, which specifically tested this ability, Experiments 2 and 3 were focused on predictions about yielding in a conflict between high-ranking and low-ranking character. Even so, Chinese adults were less likely to choose the prestigious character as the winner than the UK adults. Older children also showed signs of making the distinction in relation to yielding, as they were more likely to mention the higher-ranking character yielding in the prestige scene than in the dominance scene.
One limitation of the present studies was the sample size (n = 40 per age, country), which although on par with previous work on children's reasoning about social rank (e.g. Charafeddine et al., 2015, Charafeddine et al., 2016), was not very large. Although a larger sample would have been more beneficial, the number of children in the schools we had access to logistically limited us. We hope to remedy this in our future work.
Relying on large amounts of ethnographic evidence, Fiske (1992) laid out a theory of four elementary forms of social relationships in human societies, one of which is authority ranking, which corresponds to hierarchical relationships marked by rank differences. Even though the relational model of authority ranking might be universal, it can be implemented in myriad ways. Children may be endowed with an innate knowledge of the model of hierarchical relationships (Thomsen & Carey, 2013), but they must learn its details and exactly how it operates in their particular social milieu. These experiments provide evidence for one such culturally-influenced aspect of hierarchical relationships across two cultural backdrops. The range of cultural features and cues to relationships is underexplored, as is how children come to learn them and how long it takes them to do so. We offer an initial glimpse of one particular aspect and hope that future work will go on to uncover many more.

Forager-horticulturists: Lowering the voice fundamental frequency in audio clips of men speaking increased perceptions of fighting ability but did not affect perceptions of prestige and decreased their attractiveness to women

Sexual selection for low male voice pitch among Amazonian forager-horticulturists. Kevin A. Rosenfield et al. Evolution and Human Behavior, Volume 41, Issue 1, January 2020, Pages 3-11. https://doi.org/10.1016/j.evolhumbehav.2019.07.002

Abstract: Pitch is the most perceptually salient feature of the voice, yet it is approximately five standard deviations lower in men than in women, a degree of sexual dimorphism exceeding that of all extant nonhuman apes. Evidence from Western samples suggests that low-frequency vocalizations may have augmented male mating success ancestrally by intimidating competitors and/or attracting mates. However, data are lacking from small-scale societies. We therefore investigated sexual selection on male pitch (measured by fundamental frequency, fo) in a population of Bolivian forager-horticulturists, the Tsimané. We found that experimentally lowering fo in audio clips of men speaking increased perceptions of fighting ability but did not affect perceptions of prestige and decreased their attractiveness to women. Further, men with lower speaking fo reported higher numbers of offspring, and this was mediated by the reproductive rates of men's wives, suggesting that men with lower fo achieved higher reproductive success by having access to more fertile mates. These results thus provide new evidence that men's fo has been shaped by intrasexual competition.

Who teaches children to forage among Hadza and BaYaka Hunter-Gatherers of Tanzania and Congo? Child-to-child teaching was more frequent than adult-child teaching; and children taught more with age


Who teaches children to forage? Exploring the primacy of child-to-child teaching among Hadza and BaYaka Hunter-Gatherers of Tanzania and Congo. Sheina Lew-Levy et al. Evolution and Human Behavior, Volume 41, Issue 1, January 2020, Pages 12-22. https://doi.org/10.1016/j.evolhumbehav.2019.07.003

Abstract: Teaching is cross-culturally widespread but few studies have considered children as teachers as well as learners. This is surprising, since forager children spend much of their time playing and foraging in child-only groups, and thus, have access to many potential child teachers. Using the Social Relations Model, we examined the prevalence of child-to-child teaching using focal follow data from 35 Hadza and 38 BaYaka 3- to 18-year-olds. We investigated the effect of age, sex and kinship on the teaching of subsistence skills. We found that child-to-child teaching was more frequent than adult-child teaching. Additionally, children taught more with age, teaching was more likely to occur within same-sex versus opposite-sex dyads, and close kin were more likely to teach than non-kin. The Hadza and BaYaka also showed distinct learning patterns; teaching was more likely to occur between sibling dyads among the Hadza than among the BaYaka, and a multistage learning model where younger children learn from peers, and older children from adults, was evident for the BaYaka, but not for the Hadza. We attribute these differences to subsistence and settlement patterns. These findings highlight the role of children in the intergenerational transmission of subsistence skills.


6. Discussion

The present study aimed to investigate how age, sex, and kinship influenced the teaching of subsistence skills in BaYaka and Hadza forager 3- to 18-year-olds. Our findings suggest that Hadza and BaYaka children participated in teaching, either as a teacher or as a learner, between 6 and 8 times an hour. A majority of these teaching events occurred within child dyads. Alongside research among the Aka and Ngandu (Boyette & Hewlett, 2017a; Hewlett & Roulette, 2016), Baka (Gallois, Duda, Hewlett, & Reyes-garcía, 2015), Maya (Maynard, 2002; Zarger, 2002), and Fijians (Kline, 2016), our results highlight the central role Hadza and BaYaka children play as teachers, and not just acquirers, of cultural knowledge.
Children in both populations taught more with age, with overall teaching directed to children peaking in adulthood. Teaching likely develops with age because children's teaching abilities continue to increase, and because they have more knowledge to share with others (Strauss & Ziv, 2012). Though the development of children's teaching abilities have been documented in multiple societies in the industrialized west (see Strauss & Ziv, 2012 for review), our findings lend support to a growing body of evidence demonstrating that in non-western societies, this development occurs independently of intensive formal schooling (Boyette & Hewlett, 2017a; Maynard & Tovote, 2009). Interestingly, after approximately 30, the teaching of children actually decreased with age. Since, by 30, most adults have children who are old enough to teach their younger siblings, our findings may reflect children's participation in offsetting their cost of care. Children's participation in economic activities among the Maya likely increases mother's reproductive success (Lee & Kramer, 2002). By accelerating other children's subsistence knowledge acquisition through teaching, children may be increasing their inclusive fitness by promoting sibling self-sufficiency and shortening parental inter-birth interval. Children may also be improving their individual fitness by increasing their share of parental provisioning. Furthermore, children may liberate parents to teach more complex skills to adolescents and other adults, thus reducing the cost of cumulative cultural transmission.
Consistent with kin selection theory, teaching was more likely to occur between related dyads than unrelated dyads in both groups. However, when compared to non-kin and other-kin, sibling teaching was more common among the Hadza than among the BaYaka. We interpret these findings as indicating that teaching was more likely to occur within nuclear families among the Hadza compared to the BaYaka. We propose that these findings are related to camp structure. As noted earlier, BaYaka camps are typically more compact than Hadza camps (Hewlett et al., 2019) partially because of the constraints imposed by living in a forested environment rather than in the savannah. As a result, BaYaka children are invariably in closer proximity to all other camp members while in camp, while Hadza children can more easily assort with more closely related individuals, including siblings and parents. This may result in different teaching patterns, where other-kin and non-kin play a greater role in knowledge transmission for the BaYaka, whereas for the Hadza, the nuclear family may play a greater role in knowledge transmission. An alternative explanation may be simply that, because the Hadza have more siblings than the BaYaka, the former experienced more sibling teaching than the latter. However, Blurton Jones (2016) states that the total fertility rate for the Hadza is 5.3, while, for the BaYaka, total fertility rate is reported by Hewlett (1991) as 6.2, with similar infant mortality rates (~20% Blurton Jones, Hawkes, & O'Connell, 2002; Hewlett, 1991). Furthermore, as Table 1 shows, the BaYaka had proportionally more siblings in camp than the Hadza (5% vs. 3%), making it unlikely that number of siblings in camp explains the observed difference in Hadza and BaYaka sibling teaching. Thus, our results suggest that intra-site variation in settlement structure may influence the distribution of kin teaching. Future studies should further investigate this claim.
For the BaYaka only, younger children were more likely to be taught by other children while BaYaka adolescents were more likely to be taught by adults. This finding is consistent with the multistage model of knowledge acquisition, which suggests that children develop basic skills from other children before seeking skilled adults from whom they can update their knowledge, and who might also be more willing to teach individuals with the necessary baseline competence (Henrich & Henrich, 2010; Reyes-García et al., 2016). While our data support a multistage model of learning among the BaYaka, we found little difference in teacher's age for younger and older learners among the Hadza. While unexpected, this finding may be explained by examining foraging participation. Hadza children collect between 25 and 50% and sometimes even 100% of their daily caloric needs from an early age (Crittenden et al., 2013; Hawkes et al., 1995). Although children tend to target easier to access resources such as berries and baobab when they are younger, they are provided with opportunities to practice more complex resource acquisition throughout childhood; for example, boys as young as two are made small, functional bows and arrows, and girls are provided with small, appropriately sized digging sticks (Crittenden, 2016). Unlike among the BaYaka, children are fully expected to collect food with these tools. Thus, for the Hadza, teaching by adults may primarily occur through stimulus enhancement in early life, after which children are more likely to learn complex skills through participation in foraging with other children than through teaching by adults. Though a multistage learning model where children learn with other children when younger, and by adults when older may be more common, it may nonetheless depend on the foraging niche in which learning occurs. Future studies should thus take seriously the role of ecological context when investigating the distribution of learning processes across the lifespan.
Mathematical models investigating optimal learning strategies suggest that individual learning should occur only after children have acquired knowledge socially (Aoki, Wakano, & Lehmann, 2012; Borenstein, Feldman, & Aoki, 2008; Lehmann et al., 2013). Although previous studies of play (Bock & Johnson, 2004), observation (Greenfield, 2004), and teaching (Boyette & Hewlett, 2017a) found that social learning declined with age, presumably because older individuals have begun to refine learned behavior through individual practice, our final model found only a weak negative relationship between learner's age and teaching. However, we note that learner's age was a strong negative predictor in additional models which omitted this interaction (see supplementary materials). This suggests that what might first appear to be a decreasing likelihood for older individuals to be learners is actually better explained by (a) a decrease in teaching by older individuals, due to the declining latter portion of the quadratic ‘teacher age’ curve (Fig. 1), and (b) a tendency for teachers and learners to be of similar ages, as indicated by the positive teacher/learner age interactions. In other words, the decline in teaching by older individuals is sufficient to explain the decline in learning by older individuals as well.
As in other aspects of forager life (Allen-Arave et al., 2008; Crittenden & Zes, 2015; Peterson, 1993), we found evidence for high dyadic reciprocity, and a large effect of the dyad, in teaching. Researchers working with highly stratified cultures have found collaboration to enhance children's knowledge acquisition in experimental settings (Dean, Kendal, Schapiro, Thierry, & Laland, 2012; Dunn, 1983; Laland, 2004; Tomasello, 1999; Tomasello et al., 1993; Wood, Wood, Ainsworth, & Malley, 1995). When comparing collaborative problem solving across cultures, Nielsen, Mushin, Tomaselli, and Whiten (2016) found that Australian Indigenous children collaborated significantly more than Brisbane pre-schoolers (see also Rogoff, 1998). Since collaborative learning generates new knowledge forms (Tomasello, 1999; Tomasello et al., 1993), it may be especially adaptive to foragers relying on unpredictable resources. One limitation of our study is that we examined short-term reciprocity. A long term examination of teaching may show a different, and more unidirectional, pattern. Nonetheless, future studies should examine the advantages conferred by reciprocal knowledge sharing during daily interactions in childhood.
Finally, same-sex teaching was hypothesized to increase the likelihood that children would learn sex-specific skills (Henrich & Gil-White, 2001). Same-sex bias in learning has been noted among foragers the world over (Boyette & Hewlett, 2017a; Draper, 1975; Hewlett & Cavalli-Sforza, 1986; Lew-Levy, Lavi, Reckin, Cristóbal-Azkarate, & Ellis-Davies, 2018; MacDonald, 2007b). Here, we also found strong evidence for same-sex teaching among both the BaYaka and the Hadza.

7. Implications

Taken together, this paper sheds light on the evolutionary importance of, and cross-cultural variation in, child-to-child teaching. Most studies investigating the evolution of childhood have assumed that children require provisioning until at least adolescence (Kaplan et al., 2000), yet recent studies have challenged this claim, showing that children can be, and often are, producers (Bird & Bliege Bird, 2005; Crittenden et al., 2013; Tucker & Young, 2005), that children sometimes produce a surplus of calories which can be shared with the parental generation (Crittenden et al., 2013), and that children's production contributes to parental reproduction (Kramer, 2014; Lee & Kramer, 2002). Similarly, many studies on the evolution of cumulative culture assume that transmission only or primarily occurs from parents to offspring (e.g. Shennan & Steele, 1999), and that childhood is a sensitive period for knowledge acquisition (Kaplan et al., 2000). The results of the present paper problematize these claims because they demonstrate that children are active teachers from an early age. Child-to-child teaching may be especially adaptive because it has the potential to increase children's inclusive and individual fitness by offsetting their own, and their siblings' cost of care (Konner, 1976; Lee & Kramer, 2002). Furthermore, because children can facilitate each other's knowledge acquisition in the zone of proximal development, child-to-child teaching may contribute to more rapid, and potentially less costly, knowledge transfers for basic skills (Hewlett & Cavalli-Sforza, 1986).
Our analysis was limited by the fact that dyadic proximity data proved too difficult to collect while also keeping track of children's teaching and foraging activities. Dyadic proximity is important because individuals may choose to assort with the intent to share knowledge with each other. At least among the BaYaka, adults report inviting children to forage alongside them with the specific intent to teach subsistence skills (Lew-Levy et al., 2019). Similarly, BaYaka children sometimes preferred to forage in the absence of adults so that they could learn with their peers (Boyette & Lew-Levy, Under review). Alternatively, teaching may occur opportunistically while individuals are participating in other cooperative behaviors. For example, parents who forage with their children because they require assistants may also use a foraging trip as an opportunity to teach. Thus, future studies should examine whether teaching is independent from, or a by-product of, other social and cooperative relationships. Future studies should also examine whether cross-cultural differences in associative patterns translates to differences in teaching.
The present paper brings to light several areas for future research. Since fieldwork was only conducted during part of the year, we were unable to observe every foraging activity (e.g. kombi fishing for the BaYaka, weaver-bird collecting for the Hadza); future studies will examine how seasonal variation in child and adult foraging and diet influences how and from whom children learn (Crittenden & Schnorr, 2017; Gallois et al., 2015). In addition, as demonstrated in Table S3, we observed little teaching in especially complex domains, such as hunting and trapping. This may be because these skills are acquired later in life (Gurven, Kaplan, & Gutierrez, 2006; Ohtsuka, 1989; Walker et al., 2002). Since the age cut-off for the present study was approximately eighteen, more longitudinal studies on the distribution of knowledge acquisition across seasons, and in late adolescence and adulthood are needed. Studies comparing teaching to other social learning forms, such as observation and imitation, are also needed. Next, while the present paper considered teaching generally, future studies will examine whether different teaching types covary with the specific domain of subsistence being transmitted. Finally, the foragers with whom we worked had limited exposure to schooling. Future studies will examine how teaching patterns change with increased exposure to schools.

Evolutionary theories suggest that humans prefer sexual dimorphism in faces because masculinity in men & femininity in women may be an indicator of immune function during development; Australian data seems to confirm this

Immune function during early adolescence positively predicts adult facial sexual dimorphism in both men and women. Yong Zhi Foo et al. Evolution and Human Behavior, February 17 2020. https://doi.org/10.1016/j.evolhumbehav.2020.02.002

Abstract: Evolutionary theories suggest that humans prefer sexual dimorphism in faces because masculinity in men and femininity in women may be an indicator of immune function during development. In particular, the immunocompetence handicap hypothesis proposes that sexual dimorphism indicates good immune function during development because the sex hormones, particularly testosterone in men, required for the development of sexually dimorphic facial features also taxes the immune system. Therefore, only healthy males can afford the high level of testosterone for the development of sexually dimorphic traits without compromising their survival. Researchers have suggested that a similar mechanism via the effects of oestrogen might also explain male preferences for female femininity. Despite the prominence of the immunocompetence handicap hypothesis, no studies have tested whether immune function during development predicts adult facial sexual dimorphism. Here, using data from a longitudinal public health dataset, the Western Australian Pregnancy Cohort (Raine) Study (Generation 2), we show that some aspects of immune function during early adolescence (14 years) positively predict sexually dimorphic 3D face shape in both men and women. Our results support a fundamental assumption that facial sexual dimorphism is an indicator of immune function during the development of facial sexual dimorphism.


Sunday, February 16, 2020

From 2019... Approaching the Singularity Behind the Veil of Incomputability: On Algorithmic Governance, the Economist-as-Expert, and the Piecemeal Circumnavigation of the Administrative State

From 2019... Devereaux, Abigail, Approaching the Singularity Behind the Veil of Incomputability: On Algorithmic Governance, the Economist-as-Expert, and the Piecemeal Circumnavigation of the Administrative State (February 11, 2019). Cosmos and Taxis, vol 7 issue 1. https://cosmosandtaxis.files.wordpress.com/2019/08/devereaux_ct_vol_7_iss_1_2_rev.pdf

Abstract: Roger Koppl’s admonishment against design in his book Expert Failure is a product of the richness of the world and the symmetry-breaking properties of time. Koppl grants no special powers of vision to his experts, and thus embeds them in ongoing social process where the consequences of all policies play out in practically computable and fundamentally unknowable ways. So embedded, he demonstrates that expert rule tends to be a public bad rather than a public good. He suggests that a piecemeal deconstruction of the administrative state will grant experts less power, and free rules-making systems from the reign of idealized experts, making them less brittle to bias, ignorance, and small-groups influence. As such, they will better access the political ideal of pluralistic democracy. We call the latter Koppl’s Theorem, and propose a Corollary: rather than the piecemeal deconstruction of the administrative state, the combinatorial explosion of largely intangible computation-based goods heralded by the approach to the technological Singularity shall open ways in which social entrepreneurs can conduct a piecemeal circumnavigation of the administrative state. As both cause and consequence of the latter, untethering expertise from formal state-based institutions shall unlock the value of extra-public social entrepreneurship. We cover computability, complexity, creative processes, and the production of novelty through “togetherness,” a framework for thinking about the value created by knowledge division through time.

Keywords: algorithmic bias, epistemology, computability, economic theory
JEL Classification: B41, C63, B52

We argue that polarization increases the expected costs of engaging in corruption, especially deterring marginal low-level corruption

Polarization and Corruption in America. Mickael Melki, Andrew Pickering. European Economic Review, February 11 2020, 103397. https://doi.org/10.1016/j.euroecorev.2020.103397

Abstract: Using panel data from the US states, we document a robust negative relationship between state-level government corruption and ideological polarization. This finding is sustained when state polarization is instrumented using lagged state neighbor ideology. We argue that polarization increases the expected costs of engaging in corruption, especially deterring marginal low-level corruption. Consistent with this thesis federal prosecutorial effort falls and case quality increases with polarization. Tangible anti-corruption measures including the stringency of state ethics’ laws and independent commissions for redistricting are also associated with increased state polarization.

Keywords: CorruptionIdeological Polarization
JEL classification: K4H0


The Role of Historical Christian Missions in the Location of World Bank Aid in Africa

The Role of Historical Christian Missions in the Location of World Bank Aid in Africa. Matteo Alpino, Eivind Moe Hammersmark. The World Bank Economic Review, lhz050, February 5 2020, https://doi.org/10.1093/wber/lhz050

Abstract: This article documents a positive and sizable correlation between the location of historical Christian missions and the allocation of present-day World Bank aid at the grid-cell level in Africa. The correlation is robust to an extensive set of geographical and historical control variables that predict settlement of missions. The study finds no correlation with aid effectiveness, as measured by project ratings and survey-based development indicators. Mission areas display a different political aid cycle than other areas, whereby new projects are less likely to arrive in years with new presidents. Hence, political connections between mission areas and central governments could be one likely explanation for the correlation between missions and aid.

Keywords: development aid, Christian missions, political favoritism, Africa

JEL F35 - Foreign AidI3 - Welfare, Well-Being, and PovertyN37 - Africa; OceaniaN77 - Africa; OceaniaO19 - International Linkages to Development; Role of International Organizations


Embodied self-other overlap in romantic love: Cerebral regions known to be involved in the processing of self-related information are activated by the presentation of the beloved’s name or face

Embodied self-other overlap in romantic love: a review and integrative perspective. Virginie Quintard, Stéphane Jouffe, Bernhard Hommel, Cédric A. Bouquet. Psychological Research, February 15 2020. https://link.springer.com/article/10.1007/s00426-020-01301-8

Abstract: Romantic love has long intrigued scientists in various disciplines. Social-cognitive research has provided ample evidence for overlapping mental representations of self and romantic partner. This overlap between self and romantic partner would contribute to the experience of love and has been found to be a predictor of relationship quality. Self-partner overlap has been mainly documented at the level of conceptual or narrative self, with studies showing confusion between one’s own and partner’s identity aspects, perspectives, and outcomes. But the self is not restricted to abstract, conceptual representations but also involves body-related representations, which, research has revealed, are linked to social-cognitive processes. In this article, we review the emerging evidence that romantic love involves not only a blurring of conceptual selves but also a reduction of the distinction between self and romantic partner at a bodily level. We discuss the potential function(s) of self-other overlap in romantic relationship at the level of body-related representations and consider possible mechanisms. We conclude with possible future directions to further investigate how romantic love engages embodied self-other representations involved in social interactions.

TEC: the Theory of Event Coding
ASL: the Associative Sequence Learning


Imitation

According to TEC and the ASL model, sensorimotor learning plays an important role in the development of shared bodily representations. Importantly, while both theoretical views suggest that the main source of learning is through execution and perception of one’s own movement, the perception of others’ movements may also contribute to the development of perception–action links (Heyes & Ray 2000; Hommel, 2018). These links can be created through the establishment of associations between self-produced and others’ perceived actions, during the experience of synchronous action or when being imitated (accounting for example for mirroring of opaque actions such as facial expression—self-produced actions that one cannot see, except in a mirror). Therefore, these models predict that perception of others’ actions that often co-occur with self-performed action is more likely to trigger a perception-compatible action than other possible actions. Accordingly, people spending more time together and sharing activities, like romantic partners, should show more imitation of each other’s actions. Consistent with this proposal, in a now famous study, it was revealed that romantic partners tend to become physically similar after twenty years of marriage (Zajonc, Adelmann, Murphy, & Niedenthal, 1987). Such similarities may be explained by reciprocal imitation of the partner’s facial and other bodily expressions over time, leading partnered individuals to incorporate the bodily expressions of the other in their own body representation. A recent study by Maister and Tsakiris (2016) has more directly investigated automatic imitation (as a behavioral index of embodied self-other overlap) in romantic relationships. In their study, romantically involved participants were instructed to open or close their mouth depending on the color of a target dot while viewing pictures of their partner vs. a friend who produced either the same or a diferent action. The interference between observed and executed action (automatic imitation) was found to be larger when participants were exposed to pictures of their romantic partner’s actions compared to pictures of their friend’s actions. This may indicate greater overlap in embodied representations between romantic partners as compared to friends, even though attentional efects (more attention being drawn to pictures of the romantic partner) cannot be excluded. Increased automatic imitation of the beloved may have important consequences, as it potentially implies greater reciprocal imitation between romantic partners. Indeed, given the well documented positive outcomes of behavioral mimicry (such as liking, trust, and closeness; Chartrand & Lakin, 2013), increased imitation of the beloved may play a signifcant role in romantic relationships by fostering liking and connection between lovers. In line with this, studies based on naturalistic observation of interacting individuals have demonstrated that the amount of rapport individuals feel with each other is correlated with the assessment of the amount of posture sharing during their interactions (Lafrance, 1979; Lafrance & Broadbent, 1976). It is interesting to note that people involved in a romantic relationship are less prompt to imitate an attractive alternative, especially when passionately in love (Karremans & Verwijmeren, 2008). From this reduced mimicry of attractive alternatives, which might contribute to relationship maintenance, it is tempting to conclude that imitation has a special status within the romantic relationship.


Overlapping (conceptual) selves in romantic love

Social-psychological research has provided various conceptualizations and models of romantic love (e.g., Berscheid & Walster, 1978; Sternberg, 1986). Among these, the selfexpansion model of love is a process-oriented model conceiving romantic love as the cognitive inclusion of the (cognitive representation of) romantic partner in the self (Aron & Aron, 1996; Aron, Aron, & Norman, 2004). This model frst posits a central human motivation to extend the self, in the sense that people seek to enhance their perspectives, resources, and identities, to improve their potential efcacy (i.e. their ability to accomplish goals) (Aron & Aron, 1986; Maslow, 1967). Second, close relationships, especially romantic relationships, are assumed to provide self-expansion through the inclusion of other in the self, a process by which partners become closer and develop overlapping self representations (Aron & Aron, 1996; Aron, Mashek, & Aron, 2004). Accordingly, the self is expanded in romantic relationships by including aspects of the other in the self: the partner’s resources, perspectives, and characteristics are to some extent treated as one’s own (Aron & Aron, 1996). The experience of self-expansion is rewarding and positive, in that it broadens one’s own potentialities. It is assumed that the exhilaration associated with romantic love would be related to the experience of such self-expansion through the inclusion of partner’s characteristics into one’s self content (Aron, Norman, Aron, McKenna, & Heyman, 2000). Consistent with this view, self-expansion has been linked to positive outcomes in romantic relationships, such as admiration for the romantic partner, greater levels of satisfaction, commitment, and passion (Aron et al., 2000; Fivecoat, Tomlinson, Aron, & Caprariello, 2015; Mattingly, Lewandowski, & McIntyre, 2014; Reissman, Aron, & Bergen, 1993; Schindler, Paech, & Löwenbrück, 2015). Moreover, to the extent romantic partner’s perspectives and identities are experienced as one’s own, these partner’s characteristics thus turn out to be cognitively linked to one’s sense of self, leading to an overlap of representations of self and other (Aron & Aron, 1986). Being in love thus entails a reduced distinction, or a greater confusion, between the self and the romantic partner (Aron et al., 1991; Mashek et al., 2003; Rusbult, Martz, & Agnew, 1998). In line with the idea of self-expansion through the inclusion of the romantic partner in the self, people involved in a romantic relationship report more and wider domains (i.e. an increased diversity in self-descriptive terms) in the contents of the self-concept than singles (Aron, Paris, & Aron, 1995). This result attests to an expansion of the self-concept which is thought to arise from the inclusion of romantic partner’s characteristics into one’s own self-representation. Furthermore, consistent with the view that love involves overlapping representations of self and partner, research based on the Inclusion of the Other in the Self (IOS) scale, a pictorial measure supposed to capture self-other overlap (Aron, Aron, & Smollan, 1992), showed that participants report more overlap with their romantic partner compared to with a close friend or a family member (Acevedo, Aron, Fisher, & Brown, 2012; Quintard, Joufre, Croizet, & Bouquet, 2018). Importantly, comforting the idea that self-other overlap plays a significant role in romantic relationships, IOS scores are predictors of relationship stability over 3 months, the degree of overlap being negatively related to the likelihood of relationship dissolution (Le, Dove, Agnew, Korn, & Mutso, 2010). A key prediction of the self-expansion model is that overlapping representations of self and romantic partner elicit selfother confusion. Consistent with this prediction, studies have shown confusion between partner’s and one’s own traits (Aron et al., 1991; Mashek et al., 2003), interests, or attitudes (Aron, Steele, Kashdan, & Perez, 2006). For example, Aron et al. (1991) found slowed response times in a “me/not me” decision task (i.e., does the trait describe me?) when romantically involved participants had to evaluate traits that were relevant only for self or partner, compared to shared traits, suggesting blurred self-other boundaries in romantic love (see also Smith, Coats, & Walling, 1999). Also, the typical drop of self-esteem observed when one experiences upward social comparison is no longer present when people are outperformed by their romantic partner, especially for those reporting a high level of closeness (Lockwood, Dolderman, Sadler, & Gerchak, 2004). Thus, people do seem to experience their partner’s outcomes as their own. Results from neuroimaging studies also suggest overlapping representations of self and romantic partner. Cerebral regions known to be involved in the processing of self-related information, such as anterior cingulate cortex, fusiform and angular gyri, are activated by the presentation of the beloved’s name or face (Aron et al., 2005; Ortigue, Bianchi-Demicheli, Hamilton, & Grafton, 2007). Moreover, these cerebral activations triggered by the evocation of the beloved are positively correlated with the IOS-scores reported by participants with respect to their partner (Acevedo et al., 2012). To sum up, several lines of evidence show a blurring of the distinction between self and romantic partner, in line with the model of romantic love as an inclusion of the partner in the self. A large part of this work dealt with individuals’ traits, interests or attitudes (Aron et al., 1991, 2006; Mashek et al., 2003), that is, abstract, conceptual forms of self-representation (Gallagher, 2000; Smith, 2008). However, romantic, intimate relationships involve embodied cues such as touch, physical proximity, and shared bodily experiences (Fiske, 2004). Moreover, as speculated in early formulations of the self-expansion model of love, “in close relationships one’s body also behaves as if it is the other’s body” (Aron & Aron, 1996, p. 50), implying that the inclusion of the romantic partner in the self encompasses the body. Self-partner processing at a bodily level may be an important aspect to consider in romantic relationships in the light of empirical and theoretical research suggesting that self-other representations and social relationships are grounded in sensorimotor processing and body-related representations (e.g. Barsalou, 2010; Smith, 2008). In the next section, we provide an overview of this line of work, focusing on self-other overlap at a bodily level and its potential role in social cognition. Then, we explain why it is relevant to approach romantic love from this perspective, addressing why romantic love would affect the overlap between self and romantic partner at the bodily level.


Functional mechanisms underlying self‑other confusion

Theoretical frameworks have successfully predicted that romantic love increases self-other overlap and the sense that representations of oneself and representations of the beloved one becomes less discriminable. While the social effects and implications of this increase in representational overlap are varied and substantial, it is not yet well understood how it actually works. On the basis of ASL and TEC frameworks, we argued above that shared bodily experiences with the romantic partner may partly explain stronger bodily self-other overlap, in that it would promote the development of sensorimotor links between, or integration of, self and partner actions. But romantic love does not only, or necessarily, involve shared bodily experiences, it also entails a strong affective component and social evaluation and attitudes, which are further potentially important modulatory sources of self-other overlap. Although models acknowledge that action–perception links can be modulated by factors such as social distance or attitudes, through top-down modulation (e.g. Heyes, 2011; Chartrand & Lakin, 2013; Wang & Hamilton, 2012), they remain relatively silent regarding the cognitive mechanisms involved. However, there are frst indications that romantic love might be systematically related to, and perhaps trigger a particular cognitive-control style that favors the integration of representations, be they social or not, over discrimination. The general idea that interpersonal relations might be systematically associated with particular styles of information processing has received quite some support in recent years. For instance, high (vs. low) social power has been suggested to lead to more abstract information processing (Smith & Trope, 2006) and, conversely, abstract thinking has been shown to raise one’s subjective sense of power (Smith, Wigboldus, & Dijksterhuis, 2008). More specifcally, it has been reported that love priming (via imagination instructions), as compared to sexual priming, promotes a global, integrative processing of information in a classical local/ global processing task (Förster, Özelsel, & Epstude, 2010; see also Förster, 2009). The idea that romantic love is associated with a global processing bias, accompanied by reduced attentional selectivity (de Fockert, Caparos, Linnell, & Davidof, 2011), is consistent with the outcomes of a recent study investigating the link between romantic love and sensitivity to irrelevant information (van Steenbergen, Langeslag, Band, & Hommel, 2014). Romantically involved participants were frst required to imagine or write about a romantic event and listen to their favorite love-related music. Then they completed two conflict tasks (a Stroop and a flanker task) indexing the ability to regulate interference from irrelevant information according to situational demands. The results showed a positive association between the intensity of passionate love (as reported on the Passionate Love Scale) and the degree of interference control: more intense loving was associated with reduced selectivity, leading to a stronger impact of irrelevant information. In other words, romantic love is accompanied by a global/integrative mode of cognitive processing, which would indeed be expected to reduce self-other discrimination. This observation raises the questions (1) how the hypothetical global/integrative mode reduces discrimination between self- and other-representations, (2) why this reduction covaries with the kinds of efects and behaviors that were found to accompany romantic love, and (3) why this mode is sensitive to romantic love. Even though none of these questions has been investigated in the context of romantic love already, available fndings suggest a preliminary scenario. With respect to the frst question, general models of cognitive control have suggested that adaptive behavior requires a dynamic balance between two conficting cognitive control states, persistence/selectivity and flexibility/integration (Cools & D’Esposito, 2011; Goschke, 2003; Hommel & Wiers, 2017)—a process that has been called metacontrol (Hommel, 2015). According to a recent formulation of this view (Hommel & Wiers, 2017), a metacontrol bias toward persistence/selectivity strengthens the top-down infuence of the current goal, which focuses the system on relevant information and creates a strongly selective processing state reinforcing mutual competition between alternative representations. Conversely, a metacontrol bias toward fexibility/ integration is characterized by the weak top-down influence of the current goal and weak mutual competition between alternative representations, which widens the focus and creates a more integrative processing mode. Furthermore, the individual pattern of persistence/flexibility tradeof would emerge from an interaction between various factors known to bias cognitive control, such as genetic predisposition (Colzato, Waszak, Nieuwenhuis, Posthuma, & Hommel, 2010), cultural learning (Hommel & Colzato, 2017), task constraints (Bonnin, Gaonac’h, & Bouquet, 2011; Mekern, Sjoerds & Hommel, 2019), and afect (Dreisbach & Goschke, 2004). Various fndings have provided evidence that participants biased towards persistence/selectivity outperform others in tasks that require the exclusion of irrelevant information but perform more poorly than others in tasks that require the conjoint processing of different kinds of information, while participants biased towards fexibility/ integration show the exact opposite pattern (for reviews, see Hommel, 2015; Hommel & Colzato, 2017). From this theoretical perspective, it would make sense to assume that romantic love induces a bias towards flexibility/integration.
According to this metacontrol approach, and now we turn to the second question, romantic love should reduce the impact of the current goal on information processing, which is consistent with the observation that viewing a picture of the romantic partner is associated with a deactivation of brain areas involved in the representation of task intentions (Bartels & Zeki, 2000, 2004; Zeki & Romaya, 2010). The approach would also predict more confict between alternative representations, given that mutual inhibition is reduced, which accounts for van Steenbergen et al.’s (2014) observation that the intensity of romantic love is accompanied by a loss of conflict control. Converging evidence comes from studies in which metacontrol biases towards flexibility/integration were experimentally induced by having participants engage in a divergent thinking task, which is taxing people’s flexibility (Guilford, 1967). This manipulation has been found to evoke behavior that is very similar to that evoked by romantic love: it promotes interpersonal trust (Sellaro, Hommel, de Kwaadsteniet, van de Groep, & Colzato, 2014) and the integration of the others’ actions into one’s own task representation (Colzato, van den Wildenberg, & Hommel, 2013). Hence, romantic love may generate a similar bias towards flexibility/integration, which would account for the blurring of boundaries between the self and the romantic partner, at both conceptual and bodily levels. But why would romantic love do this? This brings us to our third question. Metacontrol biases have been shown to depend on genetic predisposition and cultural molding—two factors that are rather permanent and stable—but also on situational factors (Hommel & Colzato, 2017). The best-investigated situational factor is mood, which in the case of positive mood has been demonstrated to promote metacontrol fexibility at the cost of persistence (Dreisbach, 2006; Dreisbach & Goschke, 2004). This is interesting for our purposes for no less than four interconnected reasons. First, positive mood has also been consistently found to improve divergent thinking (Baas, de Dreu & Nijstad, 2008), the task that apparently induces similar kinds of behavior than romantic love does. Second, inducing positive mood was found to reduce interference control in confict tasks in similar ways than romantic love does (van Steenbergen, Band, & Hommel, 2010). Third, both positive mood (Akbari Chermahini & Hommel, 2012; Dreisbach et al., 2005) and divergent thinking (Akbari Chermahini & Hommel, 2010, 2012) have been shown to rely on (presumably striatal) dopamine, the neurotransmitter that is assumed to underlie metacontrol (Cools & D’Esposito, 2011; Hommel & Colzato, 2017). And, fourth, romantic love has been linked to dopaminergic transmission (Fisher et al., 2006). Taken altogether, this picture implies that engaging in romantic love and similar positive emotions are neurally represented as and/or accompanied by tonic increases of (presumably striatal) dopamine. Given that metacontrol biases are assumed to emerge from the interaction of frontal and striatal dopaminergic activity, and that increases of striatal dopamine are related to a stronger bias towards flexibility (Hommel & Colzato, 2017), this means that romantic love and flexibility biases are sharing a neuromodular mechanism that is known to generate behavior that has been observed in romantic lovers


Conclusion and future directions

In this paper, we combined theories and empirical work from contemporary social cognition, experimental psychology and neurosciences, to address the outstanding question of self-other processing in the bodily domain within romantic relationships. Extending previous research on conceptual self-other representations, the reviewed empirical findings suggest a prominent overlap between self and partner at a bodily level in romantic love. Moreover, this bodily overlap has been repeatedly found to be related to the intensity of romantic feelings. Thus, the two forms of selfhood—bodily self and conceptual self—seem to be engaged in the creation of the unique, intimate link between lovers. Building on models of perception–action links [the Theory of Event Coding (TEC) and the Associative Sequence Learning (ASL)], we propose an integrative view of causes and consequences of embodied self-other overlap in romantic relationships. We suggest that the ability to share partner’s bodily states facilitates interactions and promotes behaviors strengthening the afective bond between self and partner. Hence, this view highlights the key role of shared bodily states in social functioning as embodied cues of connectedness (Smith, 2008). Furthermore, an important and original aspect of our proposal is that it articulates the role sensorimotor and afective experiences in self-other processing. We argue that bodily experiences shared with the romantic partner and afective states may play a role in promoting the integration of self and partner bodily representations. Our proposal, which is rooted in TEC, is partly consistent with other models suggesting that action–perception links acquired through sensorimotor experience may be suficient to explain the development of social cognitive abilities such as imitation and/or empathy (e.g. Brass & Heyes, 2005; Heyes, 2018; Keysers & Gazzola, 2009). Here we suggest that to fully account for the impact of these links on social cognition, it is necessary to assume regulatory processes (metacontrol states) biasing the discrimination between self- and other-representations. By the same token, these regulatory processes allowed us to explain how afective states associated with romantic love may contribute to the reduction of bodily boundaries between self and romantic partner.
Yet, the potential role of self-partner bodily merging and the underlying mechanisms are far from being understood. Future directions can be identified to further investigate how romantic love engages embodied self-other representations involved in social interactions. Conceptual self-other overlap (as indexed for instance by IOS-scores) in the romantic context has been found to correlate with intimacy, relationship commitment and satisfaction, and to be a predictor of long term relationship stability and quality (Agnew et al., 1998; Aron et al., 1991; Le et al., 2010). Much less is known however regarding selfother overlap in the bodily domain. Future research should explore the links between embodied self-other overlap and diferent aspects of the relationship (satisfaction, self-disclosure, emotional expression, level of intimacy…). Another valuable direction would be to test how bodily self-other overlap with the romantic partner, as indexed for instance by behavioral mimicry, in the early stage of the relationship is a predictor of future relationship outcomes. More broadly, further work should examine the association between embodied self-other overlap and social cognition processes associated with the beloved. Studies already found a positive association between the intensity of romantic feelings and self-partner overlap at a bodily level (Ortigue et al., 2010; Quintard et al., 2018). This brings about the exciting question of the causal role of blurred self-other bodily boundaries to romantic feelings or attraction. A promising direction would be to test whether imitation of the beloved or procedures creating confusion between one’s own and other’s body (such as interpersonal multisensory stimulation; Tajadura-Jiménez & Tsakiris, 2014) can afect self-partner relationship. Another interesting future direction is to explore the impact of reduced bodily boundaries between self and romantic partner on the representation of peripersonal space (i.e., the space within reach). This space, which is crucial for our interaction with objects and others, has been proven to be very plastic. It is expanded in presence of another person—especially if the person is cooperative (Teneggi, Canzoneri, di Pellegrino, & Serino, 2013) and it is updated following physical changes in one’s own body (Cardini, Fatemi-Ghomi, Gajewska-Knapik, Gooch, & Aspell, 2019). Interestingly, recent work using interpersonal multisensory stimulation has demonstrated that experimentally induced reduction of self-other bodily boundaries modifes the representation of the other’s peripersonal space—in the sense of a remapping onto one’s own space (Maister, Cardini, Zamariola, Serino, & Tsakiris, 2015). Such a modification of the representation of the other’s peripersonal space may afect the way one processes events related to the other and his/her behaviors. This calls for future investigations of whether peripersonal space boundaries between romantically involved individuals may be modified and how this may relate to reduced bodily boundaries between self and romantic partner. A frst step to address this fascinating question may be to test whether the presence of the romantic partner modifies our representations of peripersonal spaces differently from other individuals. An important, yet relatively unexplored, possible efect of self-other overlap is a transfer of (usually) positive self-evaluations to the other. This kind of transfer would explain why physically touching objects triggers ownership efects (i.e. the fact that we value more objects that we own; Beggan, 1992): owned/touched objects would be valued because of their association with the (positive) self. An outstanding question is to what extent this transfer applies to one’s romantic partner, and whether self-other bodily merging may sustain such an effect. Finally, as stressed earlier, only a few studies have been devoted to the examination of basic, domain-general cognitive processes in the context of romantic love. Cognitive skills such as self-regulation and self-control (i.e. cognitive skills related to cognitive control) have been connected with relationship maintenance (Finkel & Campbell, 2001; Ritter, Karremans, & van Schie, 2010). Recent work also suggests that romantic love involves particular cognitive control states (van Steenbergen et al., 2014). Identifying potential modes of cognitive processing associated with romantic love and specifying their links with both conceptual and embodied self-other overlap is thus another crucial direction for research on romantic cognition. We hope considering these future directions will shed some new light on cognition and behaviors associated with romantic love.

Counterfactual thinking involves the mental simulation of alternatives to the past; it is associated to high neuroticism & low agreeableness

Looking Behind and Looking Ahead: Personality Differences in Counterfactual and Prefactual Thinking. Alison M. Bacon, Clare R. Walsh, Raluca A. Briazu. Imagination, Cognition and Personality, February 14, 2020. https://doi.org/10.1177/0276236620905810

Abstract: Counterfactual thinking (CFT) involves the mental simulation of alternatives to the past. In contrast, prefactual thinking (PFT) simulates potential outcomes that have yet to happen. Individuals differ in the extent to which they think in these ways, but we know little about how personality is implicated in these differences. This study investigated the relationship between Big Five personality traits and levels of spontaneous CFT and PFT embedded within a fictional diary entry. Results indicated that CFT was related to high neuroticism and low agreeableness, while PFT was related to low neuroticism and high agreeableness, as well as high extraversion. This suggests that CFT and PFT are, in part, dispositionally based and may be predicted by Big Five measures. This has implications for our understanding of individual differences in terms of the functionality of CFT and PFT and their potential influence on life outcomes.

Keywords: counterfactual thinking, prefactual thinking, Big Five, neuroticism, agreeableness, extraversion


This study did not detect any effect of daily caffeine intake on sleep duration, implying that habitual use of caffeine in real life may not coincide with laboratory findings

The dynamic relationship between daily caffeine intake and sleep duration in middle‐aged and older adults. Yueqin Hu  Katelyn Stephenson  Dalton Klare. Journal of Sleep Research, February 14 2020. https://doi.org/10.1111/jsr.12996

Abstract: The effect of caffeine on sleep has been well documented. However, most studies examined this relationship in laboratories or used a cross‐sectional design analysing between‐person differences. This study investigated the within‐person relationship between caffeine intake and sleep duration at home. In a national database, 377 participants (aged 35–85 years) completed a 7‐day diary study. Sleep duration was measured by Actigraphy and caffeine intake was self‐reported in sleep logs. Three analytic strategies were used. The average sleep duration and the average caffeine intake were not significantly correlated. Multilevel regressions using daytime caffeine intake to predict night‐time sleep, and using night‐time sleep to predict next day caffeine intake, also did not detect any significant effect. Then dynamical systems analysis was performed, where the daily change rate and change tendency of caffeine and sleep were estimated, and the relationship among these momentums was examined. Results revealed a significant effect of sleep duration on the change tendency of caffeine use: a shorter sleep duration predicted a stronger tendency to consume caffeine, and this phenomenon was only found in middle‐aged adults (aged 35–55 years) not in older adults (aged 55+). This study did not detect any effect of daily caffeine intake on sleep duration, implying that habitual use of caffeine in real life may not coincide with laboratory findings, and that using caffeine to compensate for sleep loss is the habit of middle‐aged adults, not the elderly. The advantage of using a dynamic approach to analyse interrelated processes with uncertain time lags is also highlighted.



Saturday, February 15, 2020

My English sounds better than yours: Second-language learners perceive their own accent as better than that of their peers

My English sounds better than yours: Second-language learners perceive their own accent as better than that of their peers. Holger Mitterer, Nikola Anna Eger, Eva Reinisch. PLOS February 7, 2020. https://doi.org/10.1371/journal.pone.0227643

Abstract: Second language (L2) learners are often aware of the typical pronunciation errors that speakers of their native language make, yet often persist in making these errors themselves. We hypothesised that L2 learners may perceive their own accent as closer to the target language than the accent of other learners, due to frequent exposure to their own productions. This was tested by recording 24 female native speakers of German producing 60 sentences. The same participants later rated these recordings for accentedness. Importantly, the recordings had been altered to sound male so that participants were unaware of their own productions in the to-be-rated samples. We found evidence supporting our hypothesis: participants rated their own altered voice, which they did not recognize as their own, as being closer to a native speaker than that of other learners. This finding suggests that objective feedback may be crucial in fostering L2 acquisition and reduce fossilization of erroneous patterns.

Environmental influence due to idiosyncratic experiences is dominant in the variation of intensity of aesthetic appraisal; genetic factors played a moderate role (heritability 26-41%)

Bignardi, Giacomo, Luca F. Ticini, Dirk Smit, and Tinca J. Polderman. 2020. “Domain-specific and Domain-general Genetic and Environmental Effects on the Intensity of Visual Aesthetic Appraisal.” PsyArXiv. February 7. doi:10.31234/osf.io/79nbq

Abstract: Visual aesthetic experiences are universally shared and uniquely diversified components of every human culture. The contribution of genetic and environmental factors to variation in aesthetic appraisal has rarely been examined. Here, we analysed variation in the intensity of aesthetic appraisal in 558 monozygotic and 216 dizygotic same sex adult twin pairs when they were presented with three kinds of visual stimuli: abstract objects, sceneries, and faces. We estimated twin resemblance and heritability for the three stimuli types, as well as a shared genetic factor between the three stimuli types. Genetic factors played a moderate role in the variation of intensity of aesthetic appraisal (heritability 26 to 41%). Both shared and unique underlying genetic factors significantly accounted for domain-general and domain-specific differences. Our findings are the first to show the extent to which variation in the intensity of aesthetic experiences result from the contribution of genetic and environmental factors.



Neuroticism robustly increases general dissatisfaction with welfare state programmes, yet they also appear to need these programmes more

Taking social policy personally: How does neuroticism affect welfare state attitudes? Markus Tepe  Pieter Vanhuysse. Social Policy & Administration, February 5 2020 https://doi.org/10.1111/spol.12568

Abstract: The role of the “Big Five” personality traits in driving welfare state attitudes has received scant attention in social policy research. Yet neuroticism in particular—a disposition to stress, worry, and get nervous easily—is theoretically likely to be an important driver of welfare attitudes precisely because welfare states deliver social “security” and “safety” nets. Using cross‐sectional data from the German Socio‐Economic Panel, we study three distinct attitude types (dissatisfaction with the social security system, feelings of personal financial insecurity, and preferences for state provision) and multiple social need contexts (including unemployment, ill health, old age, and nursing care). Controlling for established explanations such as self‐interest, partisanship, and socialization, neuroticism does not systematically affect support for state provision. But it robustly increases general dissatisfaction with social security, as well as financial insecurity across various need contexts. Neurotic people are thus less happy with welfare state programmes across the board, yet they also appear to need these programmes more. This trait may be an important deeper layer driving other social attitudes.




Attenuation of Deviant Sexual Fantasy across the Lifespan in U.S. Adult Nonoffending Males

Attenuation of Deviant Sexual Fantasy across the Lifespan in U.S. Adult Males. Tiffany A. Harvey, Elizabeth L. Jeglic. Psychiatry, Psychology and Law, Feb 13 2020, https://doi.org/10.1080/13218719.2020.1719376

Abstract: Deviant sexual fantasy is identified as a risk factor for sexual offending, yet no study has examined deviant sexual fantasy across the lifespan in nonoffending adult males. To bridge this gap, this study examined the frequencies of normative and deviant sexual fantasies among 318 nonoffending adult males in the United States. Participants were recruited via Amazon Mechanical Turk™. Participants took two inventories that assessed demographics and types of sexual fantasies. Normality tests, means tests, Kruskal–Wallis 1-way analyses of variance (ANOVAs), binary logistic regressions, and odds ratio post hoc analyses were conducted. Deviant sexual fantasies progressively declined across all three age groups, while normative sexual fantasy did not. Results suggest that deviant sexual fantasy changes across the lifespan. Applicability of the findings to applied settings, such as sexually violent predator evaluations, is discussed. Limitations and future considerations are addressed.

Key words: Deviant, fantasy, interest, lifespan, males, nonoffending, normative, sexual, sexual offending, United States

The Economic Consequences of Increasing Sleep Among the Urban Poor: Offering high-quality naps at the workplace increased productivity, cognition, psychological well-being, and patience

The Economic Consequences of Increasing Sleep Among the Urban Poor. Pedro Bessone, Gautam Rao, Frank Schilbach, Heather Schofield, Mattie Toma. NBER Working Paper No. 26746, February 2020. https://www.nber.org/papers/w26746

Abstract: This paper measures sleep among the urban poor in India and estimates the economic returns to increased sleep. Adults in Chennai have strikingly low quantity and quality of sleep relative to typical guidelines: despite spending 8 hours in bed, they achieve only 5.6 hours per night of sleep, with 32 awakenings per night. A three-week treatment providing information, encouragement, and sleep-related items increased sleep quantity by 27 minutes per night without improving sleep quality. Increased night sleep had no detectable effects on cognition, productivity, decision-making, or psychological and physical well-being, and led to small decreases in labor supply and thus earnings. In contrast, offering high-quality naps at the workplace increased productivity, cognition, psychological well-being, and patience. Taken together, the returns to increased night sleep are low, at least at the low-quality levels typically available in home environments in Chennai. We find suggestive evidence that higher-quality sleep improves important economic and psychological outcomes.

Supplementary materials for this paper: randomized controlled trials registry entry https://www.socialscienceregistry.org/trials/2494


Friday, February 14, 2020

Financial Robo-Analysts collectively produce a more balanced distribution of buy, hold, & sell recommendations than do human analysts, they seem less subject to behavioral biases & conflicts of interest

Coleman, Braiden and Merkley, Kenneth J. and Pacelli, Joseph, Man versus Machine: A Comparison of Robo-Analyst and Traditional Research Analyst Investment Recommendations (January 6, 2020). Available at SSRN: http://dx.doi.org/10.2139/ssrn.3514879

Abstract: Advances in financial technology (FinTech) have revolutionized various product offerings in the financial services industry. One area of particular interest for this technology is the production of investment recommendations. Our study provides the first comprehensive analysis of the properties of investment recommendations generated by “Robo-Analysts,” which are human-analyst-assisted computer programs conducting automated research analysis. Our results indicate that Robo-Analysts differ from traditional “human” research analysts across several dimensions. First, Robo-Analysts collectively produce a more balanced distribution of buy, hold, and sell recommendations than do human analysts, which suggests that they are less subject to behavioral biases and conflicts of interest. Second, consistent with automation facilitating a greater scale of research production, Robo-Analysts revise their reports more frequently than human analysts and also adopt different production processes. Their revisions rely less on earnings announcements, and more on the large, volumes of data released in firms’ annual reports. Third, Robo-Analysts’ reports exhibit weaker short-window return reactions, suggesting that investors do not trade on their signals. Importantly, portfolios formed based on the buy recommendations of Robo-Analysts appear to outperform those of human analysts, suggesting that their buy calls are more profitable. Overall, our results suggest that Robo-Analysts are a valuable, alternative information intermediary to traditional sell-side analysts.

Keywords: FinTech, Analysts, Robo-Analyst, Investment Recommendations
JEL Classification: G14, G24


Household Electrification & Economic Development--Impacts can vary even across individuals in neighboring villages: Households that were willing to pay more for a grid electrification may gain more from electrification compared to households that would only connect for free

Does Household Electrification Supercharge Economic Development? Kenneth Lee, Edward Miguel, and Catherine Wolfram. Journal of Economic Perspectives—Volume 34, Number 1—Winter 2020—Pages 122–144. https://pubs.aeaweb.org/doi/pdfplus/10.1257/jep.34.1.122

Abstract: In recent years, electrification has re-emerged as a key priority in low-income countries, with a particular focus on electrifying households. Yet the microeconomic literature examining the impacts of electrifying households on economic development has produced a set of conflicting results. Does household electrification lead to measurable gains in living standards or not? Focusing on grid electrification, we discuss how the divergent conclusions across the literature can be explained by differences in methods, interventions, potential for spillovers, and populations. We then use experimental data from Lee, Miguel, and Wolfram (2019) — a field experiment that connected randomly-selected households to the grid in rural Kenya — to show that impacts can vary even across individuals in neighboring villages. Specifically, we show that households that were willing to pay more for a grid electrification may gain more from electrification compared to households that would only connect for free. We conclude that access to household electrification alone is not enough to drive meaningful gains in development outcomes. Instead, future initiatives may work better if paired with complementary inputs that allow people to do more with power.

For supplementary materials such as appendices, datasets, and author disclosure statements, see the article page at https://doi.org/10.1257/jep.34.1.122

From 1992... Paul Romer's "Two Strategies for Economic Development: Using Ideas and Producing Ideas"

From 1992... Two Strategies for Economic Development: Using Ideas and Producing Ideas. Paul M. Romer. The World Bank Economic Review, Volume 6, Issue suppl_1, 1 December 1992, Pages 63–91, https://doi.org/10.1093/wber/6.suppl_1.63

Abstract: The key step in understanding economic growth is to think carefully about ideas. This requires careful attention to the meaning of the words that we use and to the metaphors that we invoke when we construct mathematical models of growth. After addressing these issues, this paper describes two different ways in which ideas can contribute to economic development. The history of Mauritius shows how a poor economy can benefit by using ideas from industrial countries within its borders. The history of Taiwan (China) shows how a developing economy can be pushed forward into the ranks of those that produce ideas for sale on world markets.

New neurocognitive-psychometrics account of mental speed that decomposes the relationship between mental speed and intelligence: They found that the speed of higher-order processing is greater in smarter individuals

Neurocognitive Psychometrics of Intelligence: How Measurement Advancements Unveiled the Role of Mental Speed in Intelligence Differences. Anna-Lena Schubert, Gidon T. Frischkorn. Current Directions in Psychological Science, February 13, 2020. https://doi.org/10.1177/0963721419896365

Abstract: More intelligent individuals typically show faster reaction times. However, individual differences in reaction times do not represent individual differences in a single cognitive process but in multiple cognitive processes. Thus, it is unclear whether the association between mental speed and intelligence reflects advantages in a specific cognitive process or in general processing speed. In this article, we present a neurocognitive-psychometrics account of mental speed that decomposes the relationship between mental speed and intelligence. We summarize research employing mathematical models of cognition and chronometric analyses of neural processing to identify distinct stages of information processing strongly related to intelligence differences. Evidence from both approaches suggests that the speed of higher-order processing is greater in smarter individuals, which may reflect advantages in the structural and functional organization of brain networks. Adopting a similar neurocognitive-psychometrics approach for other cognitive processes associated with intelligence (e.g., working memory or executive control) may refine our understanding of the basic cognitive processes of intelligence.

Keywords: intelligence, mental speed, psychometrics, cognitive modeling

Crimes, deterrence, & paying for more security guards: Restricting guards in sparse, rural markets and requiring guards in dense, urban markets could be socially beneficial

The Race Between Deterrence and Displacement: Theory and Evidence from Bank Robberies. Vikram Maheshri and Giovanni Mastrobuoni. The Review of Economics and Statistics, January 23, 2020. https://doi.org/10.1162/rest_a_00900

Abstract: Security measures that deter crime may unwittingly displace it to neighboring areas, but evidence of displacement is scarce. We exploit precise information on the timing and locations of all Italian bank robberies and security guard hirings/firings over a decade to estimate deterrence and displacement effects of guards. A guard lowers the likelihood a bank is robbed by 35-40%. Over half of this reduction is displaced to nearby unguarded banks. Theory suggests optimal policy to mitigate this spillover is ambiguous. Our findings indicate restricting guards in sparse, rural markets and requiring guards in dense, urban markets could be socially beneficial.

JEL classification: K42
Keywords: deterrence, displacement, spillover, policing, bank security guards