Monday, October 21, 2019

The Impact of Sugar-Sweetened Beverage Taxes on Purchases In Four Cities: We do not find impacts of the taxes in the other three cities combined

The Impact of Sugar-Sweetened Beverage Taxes on Purchases: Evidence from Four City-Level Taxes in the U.S. John Cawley, David Frisvold, David Jones. NBER Working Paper No. 26393, October 2019. https://www.nber.org/papers/w26393

Abstract: Since 2017, many U.S. cities have implemented taxes on sugar-sweetened beverages (SSBs) to decrease consumption of sugary beverages and raise revenue. In this paper, we analyze household receipt data to examine the impact of SSB taxes on households’ purchases of taxed and untaxed beverages in the four largest U.S. cities with such taxes: Philadelphia, Pennsylvania; San Francisco, California; Seattle, Washington; and Oakland, California. We estimate the impact of these taxes by comparing changes in monthly household purchases in the treatment cities to changes in one of two comparison groups: 1) areas adjacent to the treatment cities; or 2) a matched set of households nationally. We find that an increase in the beverage tax rate of 1 cent per ounce decreases household purchases of taxed beverages by 53.0 ounces per month or 12.2 percent. This impact is small in magnitude and consistent with a reduction in individual consumption of 5 calories per day per household member and eventual reduction in weight of 0.5 pounds. When we examine results separately by city, we find that the decline was concentrated in Philadelphia, where the tax decreased purchases by 27.7 percent. We do not find impacts of the taxes in the other three cities combined.

Long-lasting effects of relative age at school

Long-lasting effects of relative age at school. Lionel Page et a. Journal of Economic Behavior & Organization, October 21 2019. https://doi.org/10.1016/j.jebo.2019.10.005

Abstract: We investigate the long-lasting effects on behaviour of relative age at school. We conduct an online incentivised survey with a sample of 1007 adults, who were born at most two months before or after the school entry cut-off date in four Australian states. We find those who were among the oldest in the classroom throughout their school years display higher self-confidence, are more willing to enter in some form of competition and declare taking more risk in a range of domains in their life, compared to those who were among the youngest.

From 2012... Fascist Ecology: The "Green Wing" of the Nazi Party and its Historical Antecedents

From 2012... Fascist Ecology: The "Green Wing" of the Nazi Party and its Historical Antecedents. Peter Staudenmaier. Pomegranate The International Journal of Pagan Studies 13(10). May 2012. DOI: 10.1558/pome.v13.i10.14577

Abstract: We recognize that separating humanity from nature, from the whole of life, leads to humankind's own destruction and to the death of nations. Only through a re-integration of humanity into the whole of nature can our people be made stronger. That is the fundamental point of the biological tasks of our age. Humankind alone is no longer the focus of thought, but rather life as a whole . . . This striving toward connectedness with the totality of life, with nature itself, a nature into which we are born, this is the deepest meaning and the true essence of National Socialist thought." 1 In our zeal to condemn the status quo, radicals often carelessly toss about epithets like "fascist" and "ecofascist," thus contributing to a sort of conceptual inflation that in no way furthers effective social critique. In such a situation, it is easy to overlook the fact that there are still virulent strains of fascism in our political culture which, however marginal, demand our attention. One of the least recognized or understood of these strains is the phenomenon one might call "actually existing ecofascism," that is, the preoccupation of authentically fascist movements with environmentalist concerns. In order to grasp the peculiar intensity and endurance of this affiliation, we would do well to examine more closely its most notorious historical incarnation, the so-called "green wing" of German National Socialism. Despite an extensive documentary record, the subject remains an elusive one, underappreciated by professional historians and environmental activists alike. In English-speaking countries as well as in Germany itself, the very existence of a "green wing" in the Nazi movement, much less its inspiration, goals, and consequences, has yet to be adequately researched and analyzed. Most of the handful of available interpretations succumb to either an alarming intellectual affinity with their subject." 2 or a naive refusal to examine the full extent of the "ideological overlap between nature conservation and National Socialism." 3 This article presents a brief and necessarily schematic overview of the ecological components of Nazism, emphasizing both their central role in Nazi ideology and their practical implementation during the Third Reich. A preliminary survey of nineteenth and twentieth century precursors to classical ecofascism should serve to illuminate the conceptual underpinnings common to all forms of reactionary ecology.

From 2017... 1919–1944: Meat Propaganda, Against (Fiume, Fascism & Nazism) and Pro (US)

From 2017... 1919–1944: Meat Propaganda. Francesco Buscemi. From Body Fuel to Universal Poison pp 49-61. December 16 2017. https://link.springer.com/chapter/10.1007/978-3-319-72086-9_4

Abstract: This chapter principally analyses meat in terms of its relations to ideology. Certainly, a right-wing vegetarianism existed, and is traceable in the Italian Regency of Fiume, Fascism and Nazism, three dictatorships that ruled in today’s Croatia, Italy and Germany respectively, and threatening the entire Europe. These dictatorships were also built on what I term ‘sacred vegetarianism’, a propagandistic meat abstention descending from old Oriental myths. Nonetheless, it must be said that Fascism and Nazism were adverse to the vegetarian associations in their countries, demonstrating that sacred vegetarianism was exclusively a matter of propaganda. Starting from studies that I have already published, the first part of this chapter summarizes what I have already found and interprets the result in cultural terms. What these dictatorships communicated, in fact, became part of the collective imaginary of these nations, and thus may be considered as part of cultural history. The second part of the chapter is, conversely, devoted to the way in which meat was ideologically represented in the US, and to scientific discoveries that encouraged meat consumption. Another issue analyzed is meat in WWII, from the points of view of both the soldiers at the front and the rest of the people at home. The short story is a tale about ideology and about how it splits communities into fighting factions.

The relatively uncensored internet is replacing Kremlin-controlled TV as the public’s main window onto the world; thew image of a resurgent Russia and a decadent, devious West is becoming more difficult for Moscow to maintain


On ‘Island’ in Russian Arctic, Arrival of Fast Internet Shakes Political Calm. Anton Troianovski. The New York Times, Oct. 20, 2019. https://www.nytimes.com/2019/10/20/world/europe/russia-internet-norilsk-youtube-arctic.html

Residents of Norilsk long felt isolated from their country’s turbulence. Then a mining company strung a fiber-optic cable across 600 miles of tundra.


NORILSK, Russia — On a screen, the California sun beams through the palm fronds and the Walk of Fame gleams underfoot. This island of mines and smokestacks in the tundra has high-speed internet now, so Andrei Kurchukov watches videos about America.

Videos by one of his favorite YouTube personalities, Marina Mogilko, feature interviews with fellow Russian expatriates in the United States. “Los Angeles,” she tells her one million followers, is “where Russian dreams come true.”

“I watch her and think, alas,” Mr. Kurchukov said. “So what we’re showing about the rotting West is false.”

Closed to foreigners, unreachable by road and shrouded in darkness for 45 days a year, Norilsk, an Arctic nickel-mining hub of 180,000, is Russia’s most isolated major city. Lacking reliable digital communication with the rest of the country — “the continent,” they call it — residents used to fly home with external hard drives full of downloaded books and movies after their trips out.

Then, two years ago, the city’s mining giant, Norilsk Nickel, strung a fiber-optic cable across 600 miles of tundra and under the vast, icy Yenisey River. Amid fireworks and a concert in the central square, cheaper, faster internet suddenly replaced a slow and shaky satellite link as the city’s main data connection to the rest of the planet.

That turned Norilsk into a petri dish for a slow-motion but radical change pushing ever deeper into Russia’s hinterlands. The relatively uncensored internet is replacing Kremlin-controlled TV as the public’s main window onto the world. And as it does so, the carefully crafted image of a resurgent Russia and a decadent, devious West is becoming more difficult for Moscow’s spin doctors to maintain.

“When the internet was slow, I knew less about this bad stuff happening on the continent,” said Anastasia Oleynikova, a 49-year-old housewife, walking her three dogs on a muddy lakefront track flanked by huge, rusting pipes. Now, “It’s becoming sad and depressing to think: What has our country come to?”

An Instagram account called Norilsk Today that often posts pictures of dirty tap water and uncollected trash along with snide commentary — “At least they tell us on television that our lives are wonderful” — has amassed 54,000 followers, nearly one-third of the city’s population. With the complaints out in the open, the authorities are sometimes forced to respond.

“At the direction of the acting prosecutor,” a typical announcement in the municipal newspaper reads, “an examination has been conducted based on information posted on the social network known as ‘Instagram’ on the network known as ‘the internet.’ ”

After President Vladimir V. Putin took power in 2000, he quickly grabbed control of all of Russia’s main TV channels. Drubbed into obedience, they piped an increasingly strident narrative of a newly assertive leader facing down the West into nearly every household across the country’s 11 time zones. Critical viewpoints remained accessible online, but that mattered little from the Kremlin’s perspective: In 2014, when Mr. Putin annexed Crimea, 90 percent of Russians told independent pollster Levada that television was their primary source of news.

Over the last few years, public opinion researchers have seen a shift. This year, only 72 percent of Russians told Levada that TV was their main source of news, while the share of respondents who relied on social media to keep abreast of current events roughly doubled to 32 percent since 2014.

Even a government-run pollster, FOM, reported that the share of Russians who trust TV news fell to 36 percent in 2019, from 63 percent four years earlier.

The Russian government is spending millions to expand high-speed internet access to far-flung areas. At the same time, it has worked to expand its internet propaganda operation, criminalized insulting the government online, and consulted with China about controlling the web. But all that has not stopped online videos from the opposition leader Aleksei A. Navalny and other Putin critics from racking up tens of millions of views; those aged 18 to 24 are now more likely to turn to YouTube than to television for daily information about current events, Levada found.

The internet boom at first passed Norilsk by. The city, built in inhuman conditions by Gulag prisoners, sits next to some of the world’s largest nickel deposits, 200 miles north of the Arctic Circle. Metals leave the city’s sulfur-dioxide-belching smelters by railway for an Arctic Ocean port. Citizens, their livelihoods bound up with the mines, find it hard to leave at all. With no roads connecting the city to the outside world, constructing a land-based internet connection never made economic sense.

Residents adjusted. They created an intracity computer network that, among other things, allowed locals to download pirated movies and TV shows without connecting to the wider web. Going on vacation, several said, meant sitting in a hotel room, updating smartphone apps and taking in the bounties of the online world, even if the beach beckoned. Gamers who managed to get online to play “World of Tanks” — a popular Belarus-made computer game — learned to time their moves to take into account the delay caused by the city’s slow satellite link.

Leonid Pryadko, a miner who enjoys taking pictures in his spare time, used to enlist people leaving Norilsk to bring back downloaded YouTube videos of photography master classes, which he then shared with the city photo club. But he never sought out political content, and he said he would have never used up precious megabytes from his limited internet plan to download it.

Then, on Sept. 22, 2017, Norilsk Nickel finished a yearslong effort to string a bundle of 48 hair’s-width optical fibers over the frozen tundra, 600 miles from the city of Novy Urengoy. Part of the impetus was to modernize the company’s business processes. But a section of the 40 gigabit-per-second link was set aside for the general public, and the era of what residents call “the big internet” began.

“It was a crazy high, crazy pleasure, crazy euphoria,” Nikita Yakush, a programmer, said.

Facebook, YouTube and Instagram boomed. Even two years later, the Siberian telecommunications provider that services the city, Sibirskie Seti, said that Norilsk residents still consumed nearly twice as much web traffic as their other customers.

But as the internet expanded, political content became harder to avoid — “On YouTube, it’s everywhere,” Mr. Pryadko said. Mr. Yakush found out about this summer’s Moscow protests on an Instagram account specializing in cute animal videos. Mr. Pryadko learned about wildfires in Siberia that the Russian government was criticized for not doing enough to contain.

“I’ve started to worry,” he said, “about the political situation in the country, how everything happens with impunity.”

The regional office of Mr. Navalny, the opposition leader, is 900 miles away, in a basement in the Siberian metropolis of Krasnoyarsk. There, the office’s coordinator, Daniil Markelov, sees the fiber-optic line as an opportunity to penetrate a city so tightly monitored by the security services that passengers arriving on domestic flights have to go through passport control.

Working remotely, Mr. Markelov’s team produced a YouTube video this year telling the story of an allegedly wrongful property transfer engineered by the city’s mayor. The video got so much attention in Norilsk that the mayor, Rinat Akhmetchin, felt compelled to go on public television to deny any wrongdoing.

To Mr. Markelov, the power of YouTube is that people do not have to seek out political content — it comes to them, thanks to the platform’s recommendation algorithm.

“In terms of exerting political pressure, the internet coming to faraway cities is pretty amazing,” Mr. Markelov said. “It automatically politicizes people.”

From inside Norilsk, the city’s few activists are using the web to gain nationwide attention, creating a way to pressure the mayor’s office and the city’s main employer and polluter, Norilsk Nickel.

“We know we’re being seen, we’re being heard,” said Ruslan Abdullayev, a Norilsk lawyer who often campaigns against pollution and corruption. He said that the local news media used to ignore his complaints, but now that he can more easily reach a national audience online, “I don’t need them anymore.”

Whether greater access to critical information online actually leads Russians to demand more rights from their government remains to be seen. The chairman of the Norilsk City Council, Aleksandr Pestryakov, a member of Mr. Putin’s United Russia party, argued that better internet access had made people more withdrawn and less interested in taking part in public life.

“The internet allows for energy to be released and that’s it,” Mr. Pestryakov said. “Maybe some person would have been ready to say something against the authorities and go out on the street. But the internet lets him do that and stay on the couch by the television, and everything is great.”

Vitaly Bolnakov, a lawyer and activist, used the web to find out how to marry his same-sex partner. The couple last year flew to Denmark, got their marriage certificate, and posted a detailed how-to on a Russian L.G.B.T. online forum.

Asked about his future plans, Mr. Bolnakov jerked his thumb at the miniature American and Canadian flags mounted on his apartment wall. Watching YouTube, he said, has made him more of a “Russophobe.” He sees how often his fellow Russians’ rights are violated by the state and how little his countrymen stand up for them.

The internet will not change the fact that Mr. Putin controls a sprawling security apparatus capable of putting down any revolt, he says. But at least people now find it easier to make fun of their government.

“The internet can’t change anything cardinally, but morally it puts them down,” Mr. Bolnakov said of the authorities. “They’re being laughed at, you understand?”

Violent video game play can alter how people process social information: Improved subjective fighting ability is a reinforcing feature of violent video games that may make them highly attractive to players

Violent video game play, gender, and trait aggression influence subjective fighting ability, perceptions of men's toughness, and anger facial recognition. Thomas F. Denson et al. Computers in Human Behavior, October 21 2019, 106175. https://doi.org/10.1016/j.chb.2019.106175

Highlights
•    Playing violent video games reduced facial anger recognition.
•    Playing violent video games increased subjective fighting ability.
•    Playing violent video games reduced perceptions of other men's toughness.
•    Together results suggest violent video games enhance a readiness to fight.
•    These effects of violent video games may contribute to gaming disorders.

Abstract: Violent video game play can alter how people process social information. We examined the extent to which violent video game play influenced anger facial recognition, perceptions of one's own fighting ability, and perceptions of others' toughness. In three experiments (N = 868), participants were randomly assigned to play a violent or non-violent video game in the laboratory for 15 min (Experiments 1 and 2) or online for 5 min (Experiment 3). Participants then completed anger recognition tasks. Participants also indicated when they would back out of a physical confrontation with images of men that morphed from feminine to masculine. They rated these same target images on how tough they were and how much they could bench press. Participants rated themselves on how well they would fare in a fight against the men. Although not perfectly replicated, the general pattern of findings suggest that violent video game play impaired anger recognition, increased players' self-perceived fighting ability and reduced perceptions of the target men's toughness. Several effects were moderated by gender and/or trait aggression. These results provide insight into improved subjective fighting ability as a reinforcing feature of violent video games that may make them highly attractive to players.

Associations between adolescent media use, mental health, and risky sexual behaviors: Both social media and hours spent watching TV had negligible impacts on risky sexual behaviors

Associations between adolescent media use, mental health, and risky sexual behaviors. Renae A. Merrill, Xinya Liang. Children and Youth Services Review, Volume 103, August 2019, Pages 1-9. https://doi.org/10.1016/j.childyouth.2019.05.022

Highlights
•    Social media consumption and TV may not be practically associated with poorer mental health.
•    Both social media and hours spent watching TV had negligible impacts on risky sexual behaviors.
•    Adolescents who engaged in risky sexual behaviors reported overall poorer mental health.

Abstract: Guided by the ecological “technosystem,” data was examined from 13,156 adolescents completing the CDC's 2015 Youth Risk Behavior Surveillance System (YRBSS) looking for associations between television, social media, depressive symptoms, suicidality, and sexual risk behaviors. Regression results indicate media use is not an important factor in adolescents' internalizing and externalizing problems. Social media and television are unlikely the contributors to both mental health and risky sexual behaviors. Findings from this research are important for future studies that focus on multi-systemic prevention and intervention efforts aimed at promoting adolescent resiliency, particularly among vulnerable youth who are most susceptible to media influences.

Sunday, October 20, 2019

Men’s Bodily Attractiveness: Women’s preferences provided only partial support for our hypotheses that women will prefer muscles that most reliably differentiate between potential mates to be larger

Men’s Bodily Attractiveness: Muscles as Fitness Indicators. Patrick K. Durkee et al. Evolutionary Psychology, Volume 17 issue 2, June 5, 2019. https://doi.org/10.1177/1474704919852918

Abstract: Bodily attractiveness is an important component of mate value. Musculature—a crucial component of men’s bodily attractiveness—provides women with probabilistic information regarding a potential mate’s quality. Overall musculature is comprised of several muscle groups, each of which varies in information value; different muscles should be weighted differently by attractiveness-assessment adaptations as a result. In the current study, women and men (N = 1,742) reported size preferences for 14 major muscle groups. Women’s reported preferences provided only partial support for our hypotheses that women will prefer muscles that most reliably differentiate between potential mates to be larger; men tended to prefer larger upper-body muscles. We discuss possible interpretations of these mixed findings. Ultimately, our findings suggest that attractiveness-assessment adaptations are sensitive to the information contained within specific muscle groups and they highlight the potential for additional research on the nuances of bodily attractiveness assessment.

Keywords muscles, attractiveness assessment, evolved preferences, mate value

On average it takes a 30% increase in GDP to raise happiness by the amount that a year of war causes it to fall

Historical analysis of national subjective wellbeing using millions of digitized books. Thomas T. Hills, Eugenio Proto, Daniel Sgroi & Chanuki Illushka Seresinhe. Nature Human Behaviour, October 14 2019. https://www.nature.com/articles/s41562-019-0750-z

Abstract: In addition to improving quality of life, higher subjective wellbeing leads to fewer health problems and higher productivity, making subjective wellbeing a focal issue among researchers and governments. However, it is difficult to estimate how happy people were during previous centuries. Here we show that a method based on the quantitative analysis of natural language published over the past 200 years captures reliable patterns in historical subjective wellbeing. Using sentiment analysis on the basis of psychological valence norms, we compute a national valence index for the United Kingdom, the United States, Germany and Italy, indicating relative happiness in response to national and international wars and in comparison to historical trends in longevity and gross domestic product. We validate our method using Eurobarometer survey data from the 1970s and demonstrate robustness using words with stable historical meanings, diverse corpora (newspapers, magazines and books) and additional word norms. By providing a window on quantitative historical psychology, this approach could inform policy and economic history.


There are several ungated versions, among them one in 2015 (!): https://www.iza.org/publications/dp/9195/historical-analysis-of-national-subjective-wellbeing-using-millions-of-digitized-books

Analyses of data from a pilot experiment (n = 54) and a pre-registered experiment (n = 171) provides no evidence that mindfulness meditation increases political tolerance

Petersen, Michael Bang, and Panagiotis Mitkidis. 2019. “A Sober Second Thought? A Pre-registered Experiment on the Effects of Mindfulness Meditation on Political Tolerance.” PsyArXiv. October 20. doi:10.31234/osf.io/ksy37

Abstract: Mindfulness meditation is increasingly promoted as a tool to foster more inclusive and tolerant societies and, accordingly, meditation practice has been adopted in a number of public institutions including schools and legislatures. Here, we provide the first empirical test of the effects of mindfulness meditation on political and societal attitudes by examining whether completion in a 15-minute mindfulness meditation increases tolerance towards disliked groups relative to relevant control conditions. Analyses of data from a pilot experiment (N = 54) and a pre-registered experiment (N = 171) provides no evidence that mindfulness meditation increases political tolerance. Furthermore, exploratory analyses show that individual differences in trait mindfulness is not associated with differences in tolerance. These results suggest that there is reason to pause recommending mindfulness meditation as a way to achieve democratically desirable outcomes or, at least, that short-term meditation is not sufficient to generate these.

Check also ‘I Do Not Exist’: Pathologies of Self Among Western Buddhists. Judith Pickering. Journal of Religion and Health, June 2019, Volume 58, Issue 3, pp 748–769. https://www.bipartisanalliance.com/2019/07/i-do-not-exist-pathologies-of-self.html

Mindfulness not related to behavioral & speech markers of emotional positivity (or less negativity), interpersonally better connected (quality or quantity), or prosocial orientation (more affectionate, less gossipy or complaining)Dispositional mindfulness in daily life:
Deanna M. Kaplan, L. Raison, Anne Milek, Allison M. Tackman, Thaddeus W. W. Pace, Matthias R. Mehl. PLOS, https://www.bipartisanalliance.com/2018/11/mindfulness-not-related-to-behavioral.html


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There is reason to pause recommending mindfulness meditation as a way to achieve democratically desirable outcomes like tolerance for disliked groups

Disgust Proneness and Personal Space in Children

Disgust Proneness and Personal Space in Children. Anne Schienle, Daniela Schwab. Evolutionary Psychology, September 18, 2019. https://doi.org/10.1177/1474704919870990

Abstract: Individuals vary in their personal space (PS) size as reflected by the preferred distance to another person during social interactions. A previous study with adults showed that pathogen-relevant disgust proneness (DP) predicted PS magnitude. The present study investigated whether this association between DP and PS already exists in 8- to 12-year-old children (144 girls, 101 boys). The children answered a disgust questionnaire with the two trait dimensions “core disgust (contact with spoiled food and poor hygiene) and “death-relevant disgust” (imagined contact with dead and dying organisms). PS magnitude was assessed with a paper–pencil measure (drawing a PS bubble; Experiment 1) or with the stop-distance task (preferred distance to an approaching woman or man; Experiment 2). In both experiments, only death-related disgust predicted PS magnitude and only if the approaching person was male. The current study questions the relevance of pathogen-related disgust in children for regulating interpersonal distance.

Keywords personal space, disgust proneness, children

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Over the course of human evolution, physical proximity to others has often been associated with an increased vulnerability to interpersonal violence and infectious disease (Neuberg & Schaller, 2016). Even today, most people would not consider it wise to spend too much time in close proximity to people that are displaying overtly aggressive behavior or recognizable symptoms of illness, as the first characteristic implies an increased risk for physical harm, whereas the second a transmission of pathogens. Both types of these threats elicit specific emotions fear and disgust, which in turn facilitate certain behavioral strategies, such as escape and active avoidance/rejection (Cottrell & Neuberg, 2005).
These behaviors regulate interpersonal distance or “personal space” (PS). PS is defined as the region immediately surrounding our bodies. It can be conceptualized as an imaginary safety zone that should not be invaded by others (Hayduk, 1978). This zone has a variable magnitude, which is influenced by several characteristics of the approaching person as well of the person who is approached. For instance, biological sex moderates PS size. Women typically choose a greater distance to a male stranger relative to a female they have never met before. From a bio-evolutionary perspective, this response tendency seems to be adaptive because men are more physically aggressive than women and were historically more likely to participate in violent conflicts (Neuberg & Schaller, 2016).
Emotional states are also associated with PS size. We allow a smaller distance when we are happy and when someone is approaching us with a friendly face (Gessaroli, Santelli, di Pellegrino, & Frassinetti, 2013). On the other hand, facial expressions of anger lead to increased arousal and withdrawal even in very young children (4–24 months old; e.g., LoBue, Buss, Taber-Thomas, & Pérez-Edgar, 2017). There is also disgust-based interpersonal distancing. We try to maintain a greater distance to people who provoke feelings of disgust (e.g., because of signs of illness). Blacker and LoBou (2016) showed that children aged 6–7 years chose a greater distance to a confederate who was described as being sick. The best predictor of avoidance was the child’s knowledge about illness transmission and possible outcomes.
Finally, certain personality traits are associated with PS preferences. PS tends to be larger among anxious and introverted individuals (e.g., Pedersen, 1973; Sambo & Iannetti, 2013). Park (2015) conducted the first study on the association between the personality trait disgust proneness (DP) and PS size. He showed that individual differences in pathogen-relevant DP predicted PS magnitude independent of trait anxiety and introversion in a sample of adults. DP is the temporally stable tendency of an individual to experience disgust across different situations (Schienle & Rohrmann, 2011).
Disgust researchers generally agree that DP is a multidimensional construct (e.g., Olatunji et al., 2009; Tybur, Lieberman, & Griskevicius, 2009; Tybur, Lieberman, Kurzban, & DeScioli, 2013). For example, Olatunji et al. (2009) conducted a large cross-cultural study to evaluate the factor structure of DP in eight countries. The authors identified three central dimensions labeled “core disgust” (e.g., “You are about to drink a glass of milk when you smell that it is spoiled”), “contamination disgust” (e.g., “I probably would not go to my favorite restaurant if I found out that the cook had a cold”), and “animal-reminder disgust” (e.g., “It would bother me tremendously to touch a dead body”). With partial overlap, Tybur, Lieberman, and Griskevicius (2009) and Tybur, Lieberman, Kurzban, and DeScioli (2013) described three DP domains with the functions of pathogen avoidance and functional decision-making in the domains of mate choice and morality.
These examples demonstrate that very consistently a disgust factor related to contamination risk could be identified. This factor is part of a disease-avoidance mechanism that motivates specific behaviors (e.g., grooming, cleaning, avoidance, distancing) aiming at reducing the risk of pathogen transmission (e.g., Tybur et al. 2009). A similar disgust dimension has also been identified in children. Schienle and Rohrmann (2011) constructed a DP measure for children. Two interrelated disgust factors were identified: core disgust and “death-related disgust.” The latter factor corresponds to the factor animal-reminder disgust as described by Olatunji et al. (2009) for adults.
The present investigation analyzed whether DP (core disgust; death-related disgust) is associated with PS size in children. Two different PS tasks were employed. In Experiment 1, 110 children were asked to draw a PS bubble around a silhouette representing their own person in order to describe the preferred interpersonal distance to a woman and a man. In the second experiment with 135 children, the stop-distance task (Kennedy, Gläscher, Tyszka, & Adolphs, 2009) was conducted. A female and a male adult slowly approached the children, who were instructed that the confederate would walk toward them until they said stop.

Male Vocal Quality and Its Relation to Females’ Preferences

Male Vocal Quality and Its Relation to Females’ Preferences. Alexandre Suire, Michel Raymond, Melissa Barkat-Defradas. Evolutionary Psychology, September 30, 2019. https://doi.org/10.1177/1474704919874675

Abstract: In both correlational and experimental settings, studies on women’s vocal preferences have reported negative relationships between perceived attractiveness and men’s vocal pitch, emphasizing the idea of an adaptive preference. However, such consensus on vocal attractiveness has been mostly conducted with native English speakers, but a few evidence suggest that it may be culture-dependent. Moreover, other overlooked acoustic components of vocal quality, such as intonation, perceived breathiness and roughness, may influence vocal attractiveness. In this context, the present study aims to contribute to the literature by investigating vocal attractiveness in an underrepresented language (i.e., French) as well as shedding light on its relationship with understudied acoustic components of vocal quality. More specifically, we investigated the relationships between attractiveness ratings as assessed by female raters and male voice pitch, its variation, the formants’ dispersion and position, and the harmonics-to-noise and jitter ratios. Results show that women were significantly more attracted to lower vocal pitch and higher intonation patterns. However, they did not show any directional preferences for all the other acoustic features. We discuss our results in light of the adaptive functions of vocal preferences in a mate choice context.

Keywords attractiveness, fundamental frequency, formants, intonation, breathiness, roughness, mate choice


Check also Human vocal behavior within competitive and courtship contexts and its relation to mating success. Alexandre Suire, Michel Raymond, Melissa Barkat-Defradas. Evolution and Human Behavior, https://www.bipartisanalliance.com/2018/07/men-displaying-faster-articulation-rate.html: Men displaying faster articulation rate and louder voices reported significantly more sexual partners


Politically Motivated Causal Evaluations of Economic Performance: Despite being shown identical data, participants differed in their judgments of the graphs along party lines

Politically Motivated Causal Evaluations of Economic Performance. Zachary A. Caddick  Benjamin M. Rottman. Department of Psychology, University of Pittsburgh. http://www.lrdc.pitt.edu/rottman/pubs/38/2019CaddickRottmanCogSci.pdf

Abstract: The current study seeks to extend research on motivated reasoning by examining how prior beliefs influence the interpretation of objective graphs displaying quantitative information. The day before the 2018 midterm election, conservatives and liberals made judgments about four economic indicators displaying real-world data of the US economy. Half of the participants were placed in an 'alien cover story' condition where prior beliefs were reduced under the guise of evaluating a fictional society. The other half of participants in the 'authentic condition' were aware they were being shown real-world data. Despite being shown identical data, participants in the Authentic condition differed in their judgments of the graphs along party lines. The participants in the Alien condition interpreted the data similarly, regardless of politics. There was no evidence of a „backfire‟ effect, and there was some evidence of belief updating when shown objective data.

Keywords: motivated reasoning; politics; biases; reasoning; decision-making

Introduction

Previous research has shown that individuals often reason differently about information depending on whether it is congruent with their prior beliefs. Individuals tend to more easily accept information that is congruent with prior beliefs and desires and discount information that is incongruent with prior beliefs and desires. This process is known as motivated reasoning. In the current research, we studied the influence of political attitudes on how people interpret time series graphs of the economy. This research is at the intersection of two fields: causal reasoning about time series data, and motivated reasoning.


Motivated Reasoning and Causal Reasoning: Similarities and Differences

The fields of motivated reasoning and causal reasoning have long been intimately connected in certain ways, yet also distant in other ways. The current research aims to advance both of these fields, and to advance research on the intersection of the two.

In one aspect, these two fields have studied similar questions about the role of prior beliefs and desires on the acceptance or rejection of new information. On the causal reasoning side, there has been considerable research into how people incorporate new information with prior causal beliefs (e.g., Alloy & Tabachnik, 1984). Furthermore, many of the particular topics that have been studied in the field of motivated reasoning have had to do with causal or at least predictive relations. For example, in a seminal work on motivated reasoning, Kunda (1987) found that people tend to believe that other people who have attributes similar to themselves are less likely to get divorced than people with dissimilar attributes. Note how in this study, the attribute is as a potential cause or predictor of the effect (divorce). Other research on motivated reasoning that is less directly related to causation still often studies acceptance of causalscientific explanations, for example, about global warming (Campbell & Kay, 2014).

On the other hand, there are also important differences between these fields. First, causal learning has traditionally been focused on the rational (Bayesian) updating of beliefs given new information, whereas motivated reasoning has focused on affective reasons for failing to update beliefs. A second difference, more relevant to the current research, is that most research on causal reasoning has focused on the inferential process - how a learner infers a cause-effect relationship from a set of data. In contrast, research on motivated reasoning does not involve inference. Instead, participants are typically presented with a fact or a set of facts, and the question is whether participants accept or reject the facts (e.g., Ranney & Clark, 2016).

One recent study on motivated reasoning has investigated inference from data, similar to causal reasoning research. Kahan, Peters, Dawson, and Slovic (2017) presented participants with quantitative information in 2x2 contingency tables about the number of cities that did or did not ban handguns in public and whether there was an increase or decrease in crime, and participants were asked to infer the relation between gun bans and crime. Despite being presented with quantitative data, participants were more likely to make correct inferences when the data supported their prior attitudes about guns. The current research is in a similar vein–it investigates the role of political attitudes on inferences about economic trends.

Persuasive Effects of Presidential Campaign Advertising: Effects are sometimes distinguishable from zero, but are always quite modest

Persuasive Effects of Presidential Campaign Advertising: Results of 53 Real-time Experiments in 2016. Alexander Coppock, Seth J. Hill and Lynn Vavreck. Prepared for presentation at the 2019 meeting of the American Political Science Association, Washington, D.C., August 23, 2019. https://alexandercoppock.com/papers/CHV_ads.pdf

Abstract: In this letter, we report the results of 53randomizedadvertising experiments conducted over 29 weeks on 34,000 people during the US 2016 Presidential election. Our treatments were drawn in real time from advertisements on air each week. The ads vary on many dimensions: election type (primary or general), tone (attack or promotional), sponsor (candidates or Super PACS), context (timing), and content (topics). We manipulate which ads respondents see, when they see them, whether they see more than one ad, which ad they see first, and whether they see competing, reinforcing, or no additional information. Owing to the large size of our study, the meta-analytic estimates of the average treatment effects on favorability and vote choice are sometimes distinguishable from zero, but are always quite modest, even accounting for variation across advertisements and contexts.

Check also Le Pennec, Caroline, and Vincent Pons. "Vote Choice Formation and the Minimal Effects of TV Debates: Evidence from 61 Elections in 9 OECD Countries." Harvard Business School Working Paper, No. 20-031, September 2019. https://www.bipartisanalliance.com/2019/10/tv-debates-small-effect-in-voters.html

And Testing popular news discourse on the “echo chamber” effect: Does political polarisation occur among those relying on social media as their primary politics news source? Nguyen, A. and Vu, H.T. First Monday, 24 (5), 6. Jun 4 2019. https://www.bipartisanalliance.com/2019/10/testing-popular-news-discourse-on-echo.html

And Right-Wing Populism, Social Media and Echo Chambers in Western Democracies. Shelley Boulianne, Karolina Koc-Michalska, Bruce Bimber. New Media & Society, presented, in review. Sep 2019. https://www.bipartisanalliance.com/2019/10/echo-chambers-usa-overall-we-find-no.html

And Kalla, Joshua and Broockman, David E., The Minimal Persuasive Effects of Campaign Contact in General Elections: Evidence from 49 Field Experiments (September 25, 2017). Forthcoming, American Political Science Review; Stanford University Graduate School of Business Research Paper No. 17-65. American Political Science Review. https://www.bipartisanalliance.com/2017/11/the-best-estimate-of-effects-of.html

TV debates small effect in voters, evidence from 61 elections in 9 OECD countries: Changes in individual vote choices mostly result from changes in beliefs on competing candidates

Le Pennec, Caroline, and Vincent Pons. "Vote Choice Formation and the Minimal Effects of TV Debates: Evidence from 61 Elections in 9 OECD Countries." Harvard Business School Working Paper, No. 20-031, September 2019. https://hbswk.hbs.edu/item/vote-choice-formation-and-the-minimal-effects-of-tv-debates-evidence-from-61-elections-in-9-oecd-countries

Abstract: We use 200,000 observations from repeated survey data in 61 elections and 9 OECD countries since 1952 to study the formation of vote choices and policy preferences in the electoral season and assess how TV debates contribute to this process. We find that the share of voters who state a pre-election vote intention corresponding to their final vote choice increases by 15 percentage points in the two months preceding the election. Changes in individual vote choices mostly result from changes in beliefs on competing candidates, and they generate aggregate shifts in predicted vote shares. Instead, policy preferences remain remarkably stable over time. We use an event study to estimate the impact of TV debates, campaigns’ most salient events, and find that they do not significantly affect either individual vote choice and preference formation nor aggregate vote shares. This suggests that information continuously received by voters exerts more influence on their behavior.

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These results suggest that even if voters sometimes seem relatively uninformed, their vote choices actually aggregate a lot of information, beyond just debates, and that other sources are more impactful. A possible interpretation is that voters discard candidates’ debate statements because they rationally expect them to be more biased than information coming from nonpartisan sources, or that they only pay attention to statements aligned with their existing beliefs. But existing evidence shows that some forms of partisan communication do persuade voters. An alternative interpretation is that the particular medium through which debates are broadcasted is the issue: it is difficult for candidates to change people’s minds, and this does not happen on TV or the radio. This interpretation is consistent with the fact that campaign advertisements diffused through these channels fail to affect individual vote choices (Spenkuch and Toniatti, 2018), differently from more personalized contacts such as phone calls, door-to-door visits, or townhall meetings (e.g., Arceneaux, 2007; Fujiwara and Wantchekon, 2013; Pons, 2018).

[...]

Our results also have implications for the regulation of campaigns. Since the first presidential TV debate in the U.S., in 1960, there has been a continuous and ongoing effort to diffuse this innovation to countries which have not adopted it yet (see for instance the work done by the Commission on Presidential Debates or the National Democratic Institute), and to improve debates’ format and the fairness with which they treat all competitors, including third-party candidates, where they have become a tradition(e.g., McKinney and Carlin, 2004). Our results suggest that some of this energy may be better spent in studying and reforming campaign regulations to ensure that all campaigns have equal direct access to voters; and in monitoring the most personal and tailored forms of partisan communication, on the field and in social media, toimprovethequality of information available to voters and increase the chance that their final choice corresponds to their actual preferences. This may require granting administrative bodies responsible for organizing and supervising elections more resources, while better controlling those available to candidates.


Check also Testing popular news discourse on the “echo chamber” effect: Does political polarisation occur among those relying on social media as their primary politics news source? Nguyen, A. and Vu, H.T. First Monday, 24 (5), 6. Jun 4 2019. https://www.bipartisanalliance.com/2019/10/testing-popular-news-discourse-on-echo.html

And Right-Wing Populism, Social Media and Echo Chambers in Western Democracies. Shelley Boulianne, Karolina Koc-Michalska, Bruce Bimber. New Media & Society, presented, in review. Sep 2019. https://www.bipartisanalliance.com/2019/10/echo-chambers-usa-overall-we-find-no.html

Defining pleasant touch stimuli: Using a soft material and stroking at a velocity of 3 cm/s with light force is generally considered as particularly pleasant

Defining pleasant touch stimuli: a systematic review and meta-analysis. Pankaj Taneja et al. Psychological Research, October 19 2019. https://link.springer.com/article/10.1007/s00426-019-01253-8

Abstract: Pleasantness is generally overlooked when investigating tactile functions. Addition of a pleasant stimulus could allow for a more complete characterisation of somatosensory function. The aims of this review were to systematically assess the methodologies used to elicit a pleasant sensation, measured via psychophysical techniques, and to perform a meta-analysis to measure the effect of brush stroking velocity on touch pleasantness. Eighteen studies were included in the systematic review, with five studies included in the meta-analysis. The review found that factors such as texture, velocity, force, and the duration of continuous stroking influence tactile evoked pleasantness. Specifically, using a soft material and stroking at a velocity of 3 cm/s with light force is generally considered as particularly pleasant. The meta-analysis showed that a brush stroking velocity of 30 cm/s was rated as less pleasant than 3 cm/s, on the forearm. The present study collates the factors that are most likely to provide a stimulus to elicit a pleasant sensation. The results should be important for studies requiring a well-defined pleasant stimulus including neurosensory assessment protocols, allowing for a more complete multimodality assessment of somatosensory function.

Saturday, October 19, 2019

From 2013... The Good-in-Bed Effect: College Students’ Tendency to See Themselves as Better Than Others as a Sex Partner

The Good-in-Bed Effect: College Students’ Tendency to See Themselves as Better Than Others as a Sex Partner. James K. Beggan, Jennifer A. Vencill & Sheila Garos. The Journal of Psychology, Interdisciplinary and Applied, Volume 147, 2013 - Issue 5, Pages 415-434, Jul 2013. https://doi.org/10.1080/00223980.2012.707992

ABSTRACT: Self-enhancement refers to the finding that people tend to see themselves as better than others. The present research tested whether people display self-enhancement with regard to beliefs about their competency as sexual partners (the good-in-bed effect). Participants were asked to list good and bad sexually related behaviors more frequently performed by the self or by others. Study 1 demonstrated that people selectively associate themselves with good and others with bad sexual behaviors. In Study 2, independent raters judged bad behaviors associated with the self as less negative than bad behaviors associated with others. Study 3 replicated the good-in-bed effect and also found that when the salience of the comparison between good and bad traits is increased, men are more likely than women to demonstrate the effect. Implications of the results for relationship satisfaction are considered.

Keywords: gender, self-concept, self-enhancement, sex, sexual self, stereotypes

Childhood Maltreatment, Gender Nonconformity, and Adolescent Sexual Orientation: A Prospective Birth Cohort Study

Childhood Maltreatment, Gender Nonconformity, and Adolescent Sexual Orientation: A Prospective Birth Cohort Study. Yin Xu  Sam Norton  Qazi Rahman. Child Development, October 18 2019. https://doi.org/10.1111/cdev.13317

Abstract: This study tested whether associations between childhood maltreatment and adolescent sexual orientation were accounted for by childhood gender nonconforming behavior (GNCB) in a prospective birth cohort (N = 5,007). Childhood parental maltreatment (physical and emotional) and GNCB were assessed on multiple occasions up to age 6 years, and sexual orientation at 15.5 years. Boys with a history of maltreatment were significantly more likely to be nonheterosexual. Using propensity score weighting, maltreatment was associated with a 3.5% (p = .03) increase in the prevalence of nonheterosexuality accounting for confounders not including GNCB, and by 2.9% (p = .06) when also accounting for GNCB. These findings suggest that maltreatment is associated with an increased prevalence of nonheterosexuality in boys but may be explained by confounding factors including GNCB.


Lavender vote: Partnered lesbians and gay men are more likely than comparable heterosexuals to identify with the left, support leftist policy objectives, and vote for left‐of‐centre political parties

The European lavender vote: Sexuality, ideology and vote choice in Western Europe. Stuart J Turnbull. The European Journal of Political Research, October 18 2019. https://doi.org/10.1111/1475-6765.12366

Abstract: In many European democracies, political punditry has highlighted the attempts of political parties on the left to court the “lavender vote” of lesbian, gay and bisexual individuals. This article examines the presence of a gay vote in Western Europe with a focus on assessing the role of sexuality in shaping individuals’ political preferences and voting behaviour. Empirically, the effect of sexuality on both ideological identification as well as party vote choice is analysed. Using a cumulative dataset of eight rounds of the European Social Survey between 2002–2017, this article demonstrates that partnered lesbians and gay men are more likely than comparable heterosexuals to identify with the left, support leftist policy objectives, and vote for left‐of‐centre political parties. The analysis represents the first empirical cross‐national European study of the voting behaviour of homosexual individuals and sheds new light on the importance of sexuality as a predictor of political ideology and voting behaviour within the Western European context.

Testing popular news discourse on the “echo chamber” effect: Little evidence that political polarisation occurs among those relying on social media as their primary politics news source

Testing popular news discourse on the “echo chamber” effect: Does political polarisation occur among those relying on social media as their primary politics news source? Nguyen, A. and Vu, H.T. First Monday, 24 (5), 6. Jun 4 2019. http://eprints.bournemouth.ac.uk/32048/

Abstract: Since 2016, online social networks (OSNs), especially their “big data” algorithm, have been intensively blamed in popular news discourse for acting as an echo chamber that entraps like-minded voters in closed ideological circles and engenders political polarisation, with serious damages to democratic processes. This study examines this “echo chamber” argument through the rather divisive case of EU politics among EU citizens. Based on an exploratory secondary analysis of the Eurobarometer 86.2 survey dataset, we investigate whether the reliance on OSNs as a primary EU politics news source can lead people to more polarisation in EU-related political beliefs and attitudes than such reliance on legacy media. We found little evidence of this polarisation, which lends credence to a rejection of the “echo chamber” argument.

Keywords: echo chamber; filter bubble; political polarisation; social news; news on social media; digital news consumption; EU politics; populism;

Check also Right-Wing Populism, Social Media and Echo Chambers in Western Democracies. Shelley Boulianne, Karolina Koc-Michalska, Bruce Bimber. New Media & Society, presented, in review. Sep 2019. https://www.bipartisanalliance.com/2019/10/echo-chambers-usa-overall-we-find-no.html

Echo Chambers, USA: Overall, we find no evidence that online/social media explain support for right-wing populist candidates & parties; use of online media decreases support for right-wing populism

Right-Wing Populism, Social Media and Echo Chambers in Western Democracies. Shelley Boulianne, Karolina Koc-Michalska, Bruce Bimber. New Media & Society, presented, in review. Sep 2019. https://academic.macewan.ca/bouliannes/files/2019/09/NMS_FINAL_March2019all.pdf

Abstract: Many observers are concerned that echo chamber effects in digital media are contributing to the polarization of publics and in some places to the rise of right-wing populism. This study employs survey data collected in France, the United Kingdom, and United States (1500 respondents in each country) from April to May 2017. Overall, we do not find evidence that online/social media explain support for right-wing populist candidates and parties. Instead, in the USA, use of online media decreases support for right-wing populism. Looking specifically at echo chambers measures, we find offline discussion with those who are similar in race, ethnicity, and class positively correlates with support for populist candidates and parties in the UK and France. The findings challenge claims about the role of social media and the rise of populism.

Keywords: populism, social media, digital media, echo chambers, political discussion, selective exposure, cross-national

Friday, October 18, 2019

Older adults were less diverse in social interaction, but more diverse in activities in the afternoons, whereas younger adults reported less diverse activities partly due to working or studying more often

Weber, C., Quintus, M., Egloff, B., Luong, G., Riediger, M., & Wrzus, C. (2019). Same old, same old? Age differences in the diversity of daily life. Psychology and Aging, Oct 2019. http://dx.doi.org/10.1037/pag0000407

Abstract: Some research suggests that compared with younger adults, older adults have more homogeneous, less diverse daily life experiences because everyday situations and activities become increasingly stable and routine. However, strong empirical tests of this assumption are scarce. In two complementary studies, we examined whether older age is associated with less diversity in daily life experiences (e.g., regarding social interaction partners, activities, and places across and within days) and, if so, to what extent health limitations account for these age differences. In Study 1, we used daily diaries to investigate diversity across days among younger (N = 246; Mage = 21.8 years, SD = 2.5) and older adults (N = 119; Mage = 67.7 years, SD = 5.3). In Study 2, we investigated diversity within days employing experience sampling methods over three weeks in an adult life span sample (N = 365; range = 14–88 years). Results showed that across and within days, the daily lives of older adults were less diverse regarding their social interaction partners. Yet, older adults reported more diversity in activities within days and across days in the afternoons, whereas younger adults reported less diverse activities partly due to working or studying more often. Age differences remained statistically significant when controlling for health limitations. We conclude that age differences in the diversity of daily life are nuanced, depending on the domain and the level of analysis.


Complexity in Assessing the Benefit vs Risk of Vaccines - Experience With Rotavirus and Dengue

Complexity in Assessing the Benefit vs Risk of Vaccines - Experience With Rotavirus and Dengue Virus Vaccines. H. Cody Meissner. JAMA. October 17, 2019. doi:10.1001/jama.2019.16206

The remarkable contribution of immunization programs to public health is recognized by most people, including those who express vaccine hesitancy. Vaccine hesitancy often is predicated on the concern of an individual or family members regarding the risk of an adverse event following immunization. But for each licensed vaccine, the relative risk of an untoward event, such as contracting the disease, is greater among those who remain unvaccinated.1 Before US Food and Drug Administration (FDA) licensure, vaccine safety must be determined by demonstration that the benefit from disease prevention exceeds the risk of adverse reactions associated with the vaccine. However, this assessment is not always straightforward and the societal perspective of regulatory and advisory bodies may conflict with the individual perspective of the patient or parent. Experience with rotavirus vaccines and, more recently, the dengue virus vaccine provides insight into the complexity of this assessment.


Rotavirus Vaccine

Prior to licensure of the first oral rotavirus vaccine, rhesus-human rotavirus reassortant-tetravalent vaccine (RRV-TV), rotavirus gastroenteritis was associated with more than 50 000 hospitalizations annually and 20 to 60 deaths among children younger than 5 years in the United States. RRV-TV prevented 70% to 100% of severe infections and 48% to 68% of rotavirus diarrheal episodes.2 During prelicensure trials of RRV-TV, 5 cases of intussusception occurred among 10 054 vaccinated individuals and 1 case of intussusception occurred among 4633 unvaccinated control individuals, a difference that was not statistically significant.2 Considering the rate of intussusception among participants did not exceed the expected rate, the assessment was made by the FDA that an association between intussusception and vaccination was unlikely; nonetheless, intussusception was included as a potential adverse reaction in the package insert. RRV-TV was licensed and routine immunization was recommended by the Advisory Committee for Immunization Practices (ACIP) and the American Academy of Pediatrics (AAP) in August 1998. Less than 1 year later, in July 1999, 15 cases of intussusception occurring after immunization had been reported to the Vaccine Adverse Events Reporting System.3 When these results became available, the ACIP and the AAP stopped the recommendation for vaccine use and the manufacturer of RRV-TV voluntarily withdrew the vaccine from the market, despite the large benefit in disease prevention from the vaccine.3
Today it is recognized that the rate of intussusception is approximately 35 cases per 100 000 children younger than 1 year, and the 2 currently available rotavirus vaccines are estimated to result in an additional 1 to 5 cases of intussusception per 100 000 children younger than 1 year (about one-tenth to one-half of the rate of 10 per 100 000 individuals following administration of RRV-TV).3 Current data suggest that approximately 40 to 120 infants in the United States develop intussusception annually after administration of currently available rotavirus vaccines.3 Because of this low association with intussusception and the ability to manage most intussusception cases with nonsurgical procedures, the overall benefit in reduction of disease burden from immunization is judged by the ACIP and the AAP to exceed the small risk.
Based on the intention to offer the greatest benefit to the greatest number of people, continued use of RRV-TV in 1999 would have been more appropriate than discontinuation of the recommendation for vaccine use. Removal of the vaccine from the market resulted in more rotavirus-related illness for a larger number of infants and their family members than would have occurred with continued use of the vaccine. The more than 5-year interval between discontinuation of RRV-TV in July 1999 and availability of a human-bovine reassortant rotavirus vaccine in February 2006 likely resulted in more than 250 000 hospitalizations and 100 deaths related to rotavirus that could have been avoided with continued use of RRV-TV (based on a calculation of 5 times the number of annual cases in the prevaccine era). The number of additional cases of intussusception following continued use of RRV-TV would have been small relative to the reduction in the disease.


Dengue Vaccine

Dengue is a mosquito-borne disease caused by a flavivirus that has spread to most tropical and many subtropical countries. The disease is caused by 4 serotypes transmitted mainly by the bite of a female Aedes aegypti or Aedes albopictus mosquito. Although most dengue infections are asymptomatic, an estimated 100 million symptomatic infections occur annually resulting in 500 000 hospitalizations and 20 000 deaths worldwide, primarily in children.4 Dengue is endemic in certain territories of the United States including Puerto Rico, Guam, American Samoa, and the US Virgin Islands. No specific therapy is available for management of dengue and disease prevention has been limited to vector control.
In May 2019 the FDA licensed the first dengue vaccine (chimeric yellow fever–dengue, tetravalent dengue vaccine [CYD-TDV]), offering an important advance in disease control. Prelicensure trials in the flavivirus-endemic Latin America, Puerto Rico, and Asia-Pacific region demonstrated a vaccine efficacy of approximately 76% against virologically confirmed symptomatic dengue cases and approximately 80% against hospitalization in vaccinated individuals aged 9 through 16 years who received 3 doses of the vaccine and were seropositive at the time of vaccination.4 Among participants seronegative for dengue, vaccine effectiveness was 38%.4 In contrast to these benefits, an increased rate of severe dengue beginning about 30 weeks after the first dose occurred among a small number of vaccinated persons who were seronegative at the time of vaccination. Immunization with CVD-TDV of an immunologically naïve person created a similar immune response to that of a seronegative person infected with a dengue virus. A second infection by a different strain is associated with a risk of immune enhancement, an incompletely understood immunopathologic response resulting in an increased risk of dengue hemorrhagic fever and dengue shock syndrome.5 The rate of hospitalization due to dengue virus infection among children 9 through 16 years of age who were seronegative at time of vaccination was 1.09% among controls and 1.57% among vaccine recipients with a hazard ratio of 1.41 (95% CI 0.74-2.68.6 Based on these data, the Vaccines and Related Biologic Advisory Committee recommended licensing of CYD-TDV only for individuals in the well-studied age group (9-16 years) living in an endemic area with a laboratory documented history of dengue infection.
Prelicensure trials demonstrated that approximately 20% of participants aged 9 to 26 years living in dengue endemic areas were seronegative for dengue at baseline. Reliable identification of individuals seronegative for dengue is difficult in regions where multiple flaviviruses circulate because of cross-reacting antibodies and limited access to a reliable serologic assay. Therefore, a recommendation for routine use of CYD-TDY without screening will result in inadvertent vaccination of some seronegative people.
The World Health Organization (WHO) recommends prevaccination screening before vaccine administration. If prescreening is not feasible, WHO suggests consideration of routine use of CYD-TDV without prescreening in countries where seropositivity for dengue is greater than 80% by 9 years of age.5 One estimate of attributable risk for a cohort of 1 million people aged 9 through 16 years with greater than 80% rate of seropositivity for dengue over 5 years projected that 12 000 hospitalizations would be avoided but an additional 1000 hospitalizations would occur, primarily among individuals who were seronegative for dengue at the time of vaccination.6 Using this estimate, a recommendation for use of CVD-TDV in areas of high dengue seroprevalence where reliable serologic testing is not available could potentially benefit as many as 12 times more people than those who may experience dengue as a consequence of vaccination.
At what threshold does a large reduction in disease burden for society justify the small risk of an adverse reaction to an individual? Considerations by the FDA when licensing a candidate vaccine and by groups that issue vaccine recommendations include the prevalence and severity of the disease being prevented, the frequency and severity of an adverse reaction following immunization, and the effectiveness of the vaccine in disease prevention in the intended target population. But considerations may differ for individuals who are more concerned about an adverse reaction developing in themselves or their children and less concerned about societal benefits. They may be misinformed or unaware that remaining unvaccinated places their child at greater risk of disease than the risk of an adverse event following vaccination. Parents who choose not to immunize their children do not fulfill their parental obligation to protect children from disease. For instance, in California, because of increasing numbers of children who were incompletely vaccinated, legislation was enacted in 2016 to eliminate personal belief exemptions to vaccination. This legislation together with educational programs has been associated with a decline in the risk of a kindergarten student having contact with an inadequately vaccinated classmate from 10% in 2013 to 5% in 2017, enhancing the health of all students.7
Although risk of a rare vaccine reaction cannot be eliminated completely, well-established monitoring and compensation programs address this issue. Surveillance for safety of all licensed vaccines is monitored in a constant process. The United States uses several programs to monitor vaccine safety, including the Vaccine Adverse Events Reporting System, the Vaccine Safety Datalink, the Post-licensure Rapid Immunization Safety Monitoring System, and the Clinical Immunization Safety Assessment Project. Any untoward event reported after vaccination is assessed carefully for a causal relationship. The Vaccine Injury Compensation Program ensures equitable and timely compensation to those who may be injured by a vaccine.8 Although these programs may not reassure all vaccine-hesitant individuals, greater awareness of these programs is important. Balancing the potential of current and future vaccines in regard to disease control (even disease elimination has been achieved globally for wild polio virus types 2 and 3) vs an untoward event is overwhelmingly favorable for individuals and society.

References and full text at the DOI above.

We investigated the possibility that “successful” psychopathic individuals exhibited greater development of neural structures that promote “successful” self-regulation; results support a compensatory model of psychopathy

An investigation of the relationship between psychopathy and greater gray matter density in lateral prefrontal cortex. Emily N. Lasko et al. Personality Neuroscience, Volume 2, 2019, e7, October 18 2019. https://doi.org/10.1017/pen.2019.8, pre-print https://psyarxiv.com/j2pwy

Abstract: Psychopathic traits predispose individuals toward antisocial behavior. Such antagonistic acts often result in “unsuccessful” outcomes such as incarceration. What mechanisms allow some people with relatively high levels of psychopathic traits to live “successful”, unincarcerated lives, in spite of their antisocial tendencies? Using neuroimaging, we investigated the possibility that “successful” psychopathic individuals exhibited greater development of neural structures that promote “successful” self-regulation, focusing on the ventrolateral prefrontal cortex (VLPFC). Across two structural magnetic resonance imaging studies of “successful” participants (Study 1: N = 80 individuals in long-term romantic relationships; Study 2: N = 64 undergraduates), we observed that gray matter density in the left and right VLPFC was positively associated with psychopathic traits. These preliminary results support a compensatory model of psychopathy, in which “successful” psychopathic individuals develop inhibitory mechanisms to compensate for their antisocial tendencies. Traditional models of psychopathy that emphasize deficits may be aided by such compensatory models that identify surfeits in neural and psychological processes.

It was widely believed that acute hunger would always undermine prosociality; these authors think it is not so

Acute hunger does not always undermine prosociality. Jan A. Häusser, Christina Stahlecker, Andreas Mojzisch, Johannes Leder, Paul A. M. Van Lange & Nadira S. Faber. Nature Communications volume 10, Article number: 4733 (2019), October 18 2019. https://www.nature.com/articles/s41467-019-12579-7

Abstract: It has been argued that, when they are acutely hungry, people act in self-protective ways by keeping resources to themselves rather than sharing them. In four studies, using experimental, quasi-experimental, and correlational designs (total N = 795), we examine the effects of acute hunger on prosociality in a wide variety of non-interdependent tasks (e.g. dictator game) and interdependent tasks (e.g. public goods games). While our procedures successfully increase subjective hunger and decrease blood glucose, we do not find significant effects of hunger on prosociality. This is true for both decisions incentivized with money and with food. Meta-analysis across all tasks reveals a very small effect of hunger on prosociality in non-interdependent tasks (d = 0.108), and a non-significant effect in interdependent tasks (d = −0.076). In study five (N = 197), we show that, in stark contrast to our empirical findings, people hold strong lay theories that hunger undermines prosociality.


Different conceptualizations of injustice/unfairness: Whereas Liberals are more likely to engage in protest when the equality and need rules are violated, Conservatives are more likely to protest when the merit rule is violated

What Is (Un)fair? Political Ideology and Collective Action. Gosia Mikołajczak, Julia C. Becker. Journal of Social and Political Psychology, Vol 7, No 2 (2019). https://jspp.psychopen.eu/article/view/1230

Abstract: The established models predicting collective action have been developed based on liberal ideas of injustice perceptions showing that progressive collective action occurs when people perceive that the equality or need rule of fairness are violated. We argue, however, that these perceptions of injustice cannot explain the occurrence of social protests among Conservatives. The present work addresses one shortcoming in collective action research by exploring the interactive role of political ideology and injustice appraisals in predicting social protest. Specifically, we focused on injustice appraisals as a key predictor of collective action and tested whether the same or different conceptualizations of injustice instigate protest among Liberals versus Conservatives using data from two studies conducted in Germany (Study 1, N = 130) and in the US (Study 2, N = 115). Our findings indicate that injustice appraisals play an equally important role in instigating social protest both among Liberals and Conservatives. As we show, however, predicting collective action among individuals across the political spectrum requires accounting for ideological preferences for different fairness rules. Whereas Liberals are more likely to engage in protest when the equality and need rules are violated, Conservatives are more likely to protest when the merit rule is violated. We recommend that studies on collective action consider not only the strength of injustice appraisals but also their content, to assess which fairness principles guide one’s perceptions of (in)justice.

Keywords: collective action; political ideology; protest behaviour; rules of fairness; social justice

Environmentalists were sought after as cooperation partners and elicited more cooperation from others, though they didn't behave more cooperatively

Pro-environmental behavior as a signal of cooperativeness: Evidence from a social dilemma experiment. Stepan Vesely, Christian A. Klöckner, Cameron Brick. Journal of Environmental Psychology, October 18 2019, 101362. https://doi.org/10.1016/j.jenvp.2019.101362

Highlights
•    One's environmental behavior influences how others see and behave towards the actor.
•    People who behave pro-environmentally are expected to be more cooperative.
•    People who behave pro-environmentally are preferred as interaction partners.
•    People who behave pro-environmentally elicit more cooperation from others.
•    Results were obtained in incentivized decision tasks.

Abstract: Pro-environmental behavior has social signaling value. Previous research suggests that enacting pro-environmental behaviors can signal certain personal characteristics, such as social status and trustworthiness, to others. Using an incentivized experiment, we show that people known to behave pro-environmentally are expected to be more cooperative, are preferred as cooperation partners, and elicit more cooperation from others. The presence of pro-environmental individuals may thus motivate others to exert more effort towards reaching cooperative goals, even in situations where individual and group goals are at odds (i.e., social dilemmas). However, people who behaved pro-environmentally were actually no more cooperative than those performing fewer pro-environmental behaviors.

Our findings suggest that the differences between conservatives and liberals in disgust sensitivity are context dependent rather than a stable personality difference

Is Disgust a “Conservative” Emotion? Julia Elad-Strenger*, Jutta Proch*, Thomas Kessler. Personality and Social Psychology Bulletin, October 16, 2019. https://doi.org/10.1177/0146167219880191

Abstract: Extant political–psychological research has identified stable, context-independent differences between conservatives and liberals in a wide range of preferences and psychological processes. One consistent finding is that conservatives show higher disgust sensitivity than liberals. This finding, however, is predominantly based on assessments of disgust to specific elicitors, which confound individuals’ sensitivity and propensity to the experience of disgust with the extent to which they find specific elicitors disgusting. Across five studies, we vary specific elicitors of disgust, showing that the relations between political orientation and disgust sensitivity depend on the specific set of elicitors used. We also show that disgust sensitivity is not associated with political orientation when measured with an elicitor-unspecific scale. Taken together, our findings suggest that the differences between conservatives and liberals in disgust sensitivity are context dependent rather than a stable personality difference. Broader theoretical implications are discussed.

Keywords disgust, conservatism, liberalism, social norms

Thursday, October 17, 2019

European Social Survey (n = 235,339): Does Gender Equality Cause Gender Differences in Values? Inconclusive results

Does Gender Equality Cause Gender Differences in Values?: Reassessing the Gender-Equality-Personality Paradox. Fors Connolly, Filip; Goossen, Mikael; Hjerm, Mikael. Sex Roles, accepted. OCt 10 2019. http://www.diva-portal.org/smash/record.jsf?pid=diva2%3A1357927&dswid=9449

Abstract: The Gender-Equality-Personality Paradox (GEPP) is the finding that gender differences in personality are at their largest in the most gender equal countries. Previous known studies have not examined this relationship over time. Examining this linkage is crucial to our understanding of gender differences and personality development. In the present study, we contrast evolutionary perspectives predicting a gender divergence in personality due to progression in gender equality against biosocial perspectives predicting convergence. Using data from all eight rounds of the European Social Survey (n = 235,339) across 32 European countries, we report three findings. First, in accordance with the evolutionary perspective, country-level gender equality is positively associated with gender differences in basic human values. Second, in accordance with the biosocial perspective, we find evidence supporting gender convergence in basic human values. Third, contradicting both evolutionary and biosocial assumptions, we find no evidence that gender equality causes gender differences in values. We argue that there is a need to explore alternative explanations to the observed cross-sectional association between gender equality and personality differences, as well as gender convergence in personality over time.

Masturbation is associated with psychopathological and reproduction health conditions: an online survey among campus male students

Masturbation is associated with psychopathological and reproduction health conditions: an online survey among campus male students. Timei Jiao, Juelei Chen & Yubai Niu. Sexual and Relationship Therapy, Oct 16 2019. https://doi.org/10.1080/14681994.2019.1677883

Abstract: In order to investigate the association between masturbation and psychopathological and reproduction relative conditions, an online survey was conducted among campus male students of Zhejiang University, which comprised of basic personal information, and questions for reproduction related health, masturbation frequency, and psychological well-being. Psychological status was evaluated with Middlesex Hospital Questionnaire (MHQ). The psychological and reproduction health related parameters were compared among the groups divided according to masturbation frequency. Finally 143 students were included in analysis. Floating anxiety, somatic, and hysteric scores were significantly associated with masturbation, with higher scores in group with highest masturbation frequency; masturbation is significantly associated with fatigue, soreness and weakness of the lumbar region, memory decline, immunity decline, insomnia dreaminess and gradual increase of frequency of masturbation, and the rates of most of the reproduction related symptoms increased accompanying the increase of the masturbation frequency. MQH scores of obsession, phobic anxiety, and depression were not associated with masturbation. It was concluded that masturbation may adversely affect psychological health as well as reproductive well-being.

Keywords: Masturbation, psychological, reproductive health, depression, anxiety

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I find this doubful. Check from 2013... Macaques: Male masturbation may help maintain a high sexual arousal to decrease the length of the next mount & increase the probability of ejaculating through mating:
Effect of mating activity and dominance rank on male masturbation among free-ranging male rhesus macaques. Constance Dubuc, Sean P. Coyne, and Dario Maestripieri. Ethology. 2013 Nov 1; 119(11): 10.1111/eth.12146. https://www.bipartisanalliance.com/2019/10/from-2013-macaques-male-masturbation.html

From 2013... Macaques: Male masturbation may help maintain a high sexual arousal to decrease the length of the next mount & increase the probability of ejaculating through mating

From 2013... Effect of mating activity and dominance rank on male masturbation among free-ranging male rhesus macaques. Constance Dubuc, Sean P. Coyne, and Dario Maestripieri
Ethology. 2013 Nov 1; 119(11): 10.1111/eth.12146.

Abstract: The adaptive function of male masturbation is still poorly understood, despite its high prevalence in humans and other animals. In non-human primates, male masturbation is most frequent among anthropoid monkeys and apes living in multimale-multifemale groups with a promiscuous mating system. In these species, male masturbation may be a non-functional by-product of high sexual arousal or be adaptive by providing advantages in terms of sperm competition or by decreasing the risk of sexually transmitted infections. We investigated the possible functional significance of male masturbation using behavioral data collected on 21 free-ranging male rhesus macaques (Macaca mulatta) at the peak of the mating season. We found some evidence that masturbation is linked to low mating opportunities: regardless of rank, males were most likely to be observed masturbating on days in which they were not observed mating, and lower-ranking males mated less and tended to masturbate more frequently than higher-ranking males. These results echo the findings obtained for two other species of macaques, but contrast those obtained in red colobus monkeys (Procolobus badius) and Cape ground squirrels (Xerus inauris). Interestingly, however, male masturbation events ended with ejaculation in only 15% of the observed masturbation time, suggesting that new hypotheses are needed to explain masturbation in this species. More studies are needed to establish whether male masturbation is adaptive and whether it serves similar or different functions in different sexually promiscuous species.

Keywords: Masturbation, auto-erotism, male-male competition, sexually-transmitted disease, sexual arousal, mating success, dominance rank, rhesus macaques

INTRODUCTION

Masturbation, or self-manipulation of the genitalia, is part of the natural behavioral repertoire of many animal species (reviewed in Bagemihl 1999; Thomsen et al. 2003; Dixson 2012), including humans (Laqueur 2003; Dixson 2012), but whether this behavior has an adaptive function is still poorly understood. Although comparative behavioral data on masturbation could help us understand the adaptive function and evolution of this behavior, very few data are available to date.

Different hypotheses have been proposed to explain the function of male masturbation (reviewed by Waterman 2010; see also Dixson 2012). The “sexual-outlet” hypothesis proposes that masturbation is a non-adaptive by-product of sexual arousal and serves as an alternative outlet to copulation (Kinsey et al. 1948; Dixson & Anderson 2004; Dixon 2012). This by-product hypothesis implies that males do not gain any fitness benefits, in terms of their health or survival, or increased mating or reproductive success, from masturbation. Second, the “ejaculate-quality-improvement” hypothesis posits that masturbation is an adaptive behavior that serves to eliminate degraded gametes or avoid polyzoospermy in order to increase the overall ejaculate quality, thus increasing the probability of impregnation when males copulate with a fertile female (Zimmerman et al. 1965; Baker & Bellis 1993, 1995; Thomsen et al. 2003; Thomsen & Soltis 2004). While suggesting very different functions of masturbation, these two hypotheses both predict that masturbation should be more frequent among males that have little or no opportunity to mate, and/or occur in periods of infrequent mating (Thomsen et al. 2003; Thomsen & Soltis 2004; Dixson & Anderson 2004; Waterman 2010; Dixon 2012). In addition, the ejaculate-quality-improvement hypothesis predicts that males who have infrequent access to females but masturbate frequently should have higher sperm quality and higher probability of impregnation when compared to males who masturbate less frequently, other things being equal. Finally, according to the “STI-reduction” hypothesis, masturbation serves to cleanse the male reproductive tract to decrease the risk of contracting sexually transmitted infections (STIs) (Waterman 2010). This hypothesis has been developed more recently to explain the behavioral pattern observed in the highly promiscuous Cape ground squirrels (Xerus inauris; Waterman 2010). Contrary to the two other hypotheses, the STI-reduction hypothesis predicts that male masturbation should be more prevalent in periods of high sexual activity, performed by males who mate successfully, and occur shortly after copulation (Waterman 2010). Moreover, it predicts that males who masturbate frequently in these circumstances should be less likely to contract sexually transmitted diseases than males who do not masturbate or do so less frequently, and should thus be in overall better health. It should be noted that all three hypotheses are based on the assumption that male masturbation typically leads to ejaculation.

Among nonhuman primates, the occurrence of male masturbation has been documented at the qualitative level for 30 species of Old World monkeys and apes, whereas it is rare or even absent in New World monkeys and prosimians (reviewed in Thomsen et al. 2003; Dixson 2012). Male masturbation is most frequent in anthropoid primates that live in multimale-multifemale groups (Thomsen et al. 2003) and have large testis volume relative to their body size (Dixson & Anderson 2004). While this observation has been interpreted as being suggestive that male masturbation is functionally linked to sperm competition (ejaculate-quality-improvement hypothesis; Thomsen et al. 2003), this observation is also consistent with the sexual-outlet hypothesis because in sexually promiscuous species “males possess neuroendocrine specializations for greater sexual arousal and performance” (Dixson & Anderson 2004, p. 366; see also Dixon 2012, p. 192). Such pattern could also be explained by the STI-hypothesis because sexually transmitted infections are more likely to spread in species with promiscuous mating system (Waterman 2010).

While no primate studies to date have directly investigated the potential fitness benefits of male masturbation, a handful of studies have investigated the functional hypotheses indirectly, by testing their predictions concerning the frequency of masturbation and its potential association with rank and mating activity within species. In free-ranging red colobus monkeys (Procolobus badius), masturbation was performed very rarely (5 instances in 8,950h of observation collected over 5 years) mainly by alpha males and specifically during intergroup encounters (i.e. when rivals are present) taking place when some females were sexually active, with no copulations reported for either resident or extra-group males (Starin 2004). Male masturbation was much more frequent in two macaques species, in which hundreds of instances were observed over less than 1000 hours of observation collected over 1–2 years (Nieuwenhuijsen et al. 1987; Thomsen & Soltis 2004). In free-ranging Japanese macaques (Macaca fuscata), masturbation is more frequent in males of lower mating success and those of lower dominance rank (Thomsen & Soltis 2004; see also Inoue, 2012). No such relation between dominance rank and masturbation frequency was revealed in captive group-living stump-tail macaques (M. arctoides; Nieuwenhuijsen et al. 1987). A closer investigation of the latter study’s data, however, revealed an opposite pattern of distribution of mating and masturbation rate between the alpha male (409 copulations vs. 30 masturbation bouts) and the beta male (30 copulations vs. 543 masturbation bouts), which suggests a relation between rank, mating, and masturbation similar to that reported in Japanese macaques (cf. Table 3 in Nieuwenhuijsen et al. 1987). Overall, the results obtained for macaques seem more consistent with the ejaculate-quality-improvement and sexual-outlet hypotheses than with the STI-reduction one.

In the present study, we examined whether and how access to fertile females influences masturbation rate in free-ranging male rhesus macaques on Cayo Santiago, Puerto Rico. Rhesus macaques are seasonal breeders and on Cayo Santiago that they live in unusually large troops (50–300 individuals). In this rhesus population, male mating and reproductive success are linked to dominance rank, although not strongly (e.g. Berard et al. 1994; Dubuc et al. 2011). High-ranking males form extended consortships with estrous females characterized by frequent copulations and ejaculations, while lower-ranking males mate less frequently and mainly through sneak copulations and short-term associations (e.g. Carpenter 1942; Altmann 1962; Chapais 1983; Berard et al. 1994; Higham et al. 2011). However, middle- and low-ranking males can still enjoy a relatively high reproductive success (e.g. Berard et al. 1994; Dubuc et al. 2011) because high-ranking males are generally unsuccessful at mate-guarding females over the entire course of their fertile phase (Dubuc et al. 2012), thus making it possible for other males to fertilize females through sneaky copulations and sperm competition (see also Bercovitch 1992). While male masturbation has long been known for this species (e.g. Carpenter 1942; Phoenix & Jenson 1973), little is known about the relationship between masturbation and mating activity. Work on captive rhesus macaques has shown that male masturbation takes place even without any sensory contact with females (e.g. Phoenix & Jenson 1973), is eliminated by castration (Phoenix & Jenson 1973; Slimp et al. 1978; Loy et al., 1984), but not by brain lesions that eliminate sexual interactions with females (Slimp et al. 1978).

Here, we explored the possible functional significance of male masturbation by investigating the correlation between masturbation frequency and male dominance rank, and investigating how mating activity influences masturbation behavior in two different ways, by testing (i) whether there is a correlation between masturbation rate and overall mating frequency, and (ii) whether or not males were more likely to masturbate on days in which they were seen mating. Based on previous findings obtained in macaques, we predicted that the pattern of male masturbations will be more consistent with the sexual-outlet and ejaculate-quality-improvement hypotheses than with the STI hypothesis. Specifically, we predicted that (1) low-ranking males and/or least successful males of a social group should be more likely to be observed masturbating, and (2) males should be more likely to masturbate on days in which they do not mate. In addition, we expected (3) masturbation to lead to ejaculation.

DISCUSSION

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In our study, masturbation that did not lead to ejaculation took place in two main contexts (25% of all masturbation bouts each): (1) males manipulated their in penis only once in a period of time in which they emitted a large amount of self-directed behaviors; and (2) males stopped masturbating and started interacting with females in a sexual context, a third of which led to mating (Fig. 3). In the remaining cases, the male changed activity or simply stopped with no obvious change of activity. Based on these observations, we propose two hypotheses to explain male masturbation in rhesus macaques. Firstly, we propose that it may be a form of self-directed behavior emitted in context of intense anxiety (Maestripieri et al. 1992), which could or could not be created by a sexual context itself (‘masturbation-as-SDB’ hypothesis). Masturbation could be more frequent among low-ranked males if their position creates more emotional stress. Alternatively, male masturbation could be aimed at maintaining high level of sexual arousal for males in order to decrease the length of the next mount series and increase the probability of ejaculating through mating (‘sexual-arousal’ hypothesis). In rhesus macaques, mount series can last from 1 to 56 minutes, and long series are more likely to be interrupted by higher-ranking males (Manson 1996). This would be more frequent among non-dominant males that have a low access to females and mate mainly during short-term associations and sneak copulations.

An unequivocal rejection of the null hypothesis that male masturbation is a non-functional by-product of frustrated sexual arousal would require evidence that inter-individual variation in masturbation behavior is associated with variation in male health, emotional stress, ejaculate quality, and/or in fertilization success. While Inoue (2012) showed no correlation between masturbation rate and reproductive success, the fact that mating rate or dominance rank was not taken into account provides little insights about whether males masturbating produced more offspring than predicted based on their mating rate. Some insights into the function of masturbation could also be provided by comparing closely-related primate species that live in multi-male multi-female groups that differ in the extent to which the alpha male effectively monopolizes access to fertile females (and in turn, the intensity of sperm competition) or in their mating pattern (i.e. multiple-mounters vs. single-mounters). Comparing prevalence of male masturbation, the frequency at which it leads to ejaculation, and context in which it takes place within these species could shed some light on whether maintaining a steady supply of high-quality sperm through frequent masturbation is needed to take full advantage of rare opportunities for copulation that become available to individuals who are otherwise consistently prevented from copulating.