Wednesday, August 21, 2019

Overweight participants craved a greater variety of high-caloric high palatable foods than normal‐weight participants at both eating events and random non‐eating moments

Food craving in daily life: comparison of overweight and normal‐weight participants with ecological momentary assessment. A. Roefs  B. Boh  G. Spanakis  C. Nederkoorn  L. H. J. M. Lemmens  A. Jansen. Journal of Human Nutrition and Dietetics, August 20 2019. https://doi.org/10.1111/jhn.12693

Abstract
Background: The present study examined food cravings in daily life by comparing overweight and normal‐weight participants right before eating events and at non‐eating moments. It was hypothesised that overweight participants would have (i) more frequent, (ii) stronger and (iii) a greater variety of high‐caloric palatable food cravings, and also would (iv) consume more high‐caloric palatable foods, than normal‐weight participants.

Methods: Ecological momentary assessment (EMA) was used to assess food craving strength and frequency, variety of specific food cravings, and food intake. Fifty‐seven overweight and 43 normal‐weight adult participants were assessed at eating events and at an average of eight random non‐eating moments per day for 2 weeks. Foods were categorised as: high‐caloric high palatable foods (HCHP), fruits and salads, staple food dishes and sandwiches, and soups and yoghurts.

Results: Overweight participants reported more frequent HCHP food cravings specifically at non‐eating moments than did normal‐weight participants. Normal‐weight participants reported more food cravings for staple foods, specifically at eating events. Moreover, overweight participants craved a greater variety of HCHP foods than normal‐weight participants at both eating events and random non‐eating moments. No other significant between‐group differences were found.

Conclusions: The results highlight the importance for obesity interventions (i) to specifically target high‐caloric palatable food cravings that are experienced during the day and are not tied to eating moments and (ii) to aim for a reduction in the variety of high‐caloric palatable food cravings. It might be fruitful to deliver treatment aimed at reducing cravings via mobile devices because this allows for easy individual tailoring and timing of interventions.

Introduction
People eat not only to satisfy homeostatic hunger, but also to satisfy cravings and hedonic hunger 1, 2. Food cravings are common 3, and people often crave foods that are high in calories and low in nutritional value 4, 5. High‐caloric food intake has been associated with weight gain and obesity 6. Furthermore, sensitivity to the rewarding properties 7 and the reinforcing value 8 of palatable foods is stronger for people with a higher body mass index (BMI) than for those with a lower BMI. The present study aimed to investigate food cravings and intake of overweight (BMI ≥ 25 kg/m2) and normal‐weight (18.5 kg/m2 ≤ BMI < 25 kg/m2) people in daily life by means of ecological momentary assessment (EMA).
Previous research on food craving, mainly relying on retrospective self‐report (questionnaire) assessment, has found that overweight people have more frequent specific food cravings, mainly for high‐caloric foods, compared to normal‐weight people 4, 9-11. In addition, a meta‐analysis has shown that craving and food‐cue reactivity are significant predictors of eating behaviour and body weight 12, as well as of a reduction of perceived self‐regulatory success in dieting 13. Accordingly, an increased food craving appears to be an important aspect of obesity. However, retrospective self‐report assessment is subject to memory recall biases: more recent and more emotionally salient memories are disproportionately often recalled 14, 15. Investigating food cravings as they occur in daily life using EMA could lead to more ecologically valid insights.
During EMA, participants receive prompts on a mobile device (e.g. smartphone) several times a day to answer questions, for example regarding mood, social circumstances and food cravings, and/or are instructed to answer questions on their phone in predefined situations (e.g. when about to eat something). EMA has the advantage that data are obtained in the moment and in daily life (ecological validity) and are not affected by retrospective memory or response bias 14. Another advantage is that participants provide multiple assessments of the included variables, allowing researchers to analyse how the variables develop over time within a participant. Thus, ‘EMA aims to minimize recall bias, maximize ecological validity and allow study of microprocesses that influence behavior in real‐world contexts’ 15. EMA conducted via an electronic device may be especially suitable to assess food cravings because of the relatively short duration of such cravings 16.
EMA studies on food craving have increasingly been published in recent years. It was found that food cravings for sweet and salty snacks increased over the day, with a reduced coherence with hunger 17. In addition, a study focusing on snacks found that most reported snacks were high‐caloric (86%) and that craving intensity was positively associated with snack consumption 18. Studies focusing on dieters found that 17% 5 to 50% 19 of daily life food cravings resulted in dietary lapses. Interestingly, the strength and the frequency of food cravings were not related to dietary restraint 5, although dieters were more likely to give in to food temptations if the craving to eat was stronger 19. With regard to body weight, it was unexpectedly found that a group of people with obesity reported fewer unresisted food cravings compared to a lean group. However, within the obese group, the fraction of unresisted food craving was positively associated with BMI 20. Because that study employed only event‐related sampling (i.e. self‐initiated measurement at eating occasions), this may be a result of BMI‐related under‐reporting.
Another aspect of food craving relates to the variety of craved foods. Although previous research has linked food intake variety to obesity 21-23, not much is known about food craving variety. Sensory‐specific satiety has been suggested to explain the link between intake variety and obesity 24, 25: satiety occurs separately for each of the sensory characteristics of different kinds of foods. Accordingly, when a large variety of foods is consumed, it will take longer for satiety to set in, which may lead to increased intake 26. In general, food cravings and the subsequent intake of these craved foods are highly positively associated 4, 11, 27, 28, with one possibility being that food craving variety is also related to obesity.
Taken together, the present study investigates how food craving frequency, strength and variety, as well as food intake, are related to weight status. The study addresses the following hypotheses: overweight participants (i) report more frequent and (ii) stronger food cravings for high‐caloric palatable foods, (iii) they crave a greater variety of high‐caloric palatable foods and (iv) they consume more high‐caloric palatable foods compared to normal‐weight participants. In addition, the association between specific food cravings and food intake is investigated. Food craving frequency, strength and variety are investigated and compared separately for eating events (i.e. that were about to occur) and non‐eating moments. There are no specific a priori hypotheses about differences between eating events and non‐eating moments in terms of food craving frequency, strength or variety.

A test of the micro‐expressions training tool: The METT group did not outperform those in the bogus training and no training groups; further, overall accuracy was slightly below chance

A test of the micro‐expressions training tool: Does it improve lie detection? Sarah Jordan  Laure Brimbal  D. Brian Wallace  Saul M. Kassin  Maria Hartwig  Chris N.H. Street. Journal of Investigative Psychology and Offender Profiling, August 20 2019. https://doi.org/10.1002/jip.1532

Abstract: The purpose of the study was to examine the effectiveness of the micro‐expressions training tool (METT) in identifying and using micro‐expressions to improve lie detection. Participants (n = 90) were randomly assigned to receive training in micro‐expressions recognition, a bogus control training, or no training. All participants made veracity judgements of five randomly selected videos of targets providing deceptive or truthful statements. With the use of the Bayesian analyses, we found that the METT group did not outperform those in the bogus training and no training groups. Further, overall accuracy was slightly below chance. Implications of these results are discussed.

Preference for high heels correlated with female self-perceived attractiveness; were most preferred in interaction with an attractive male, & least preferred in interaction with an unattractive male

Wearing high heels as female mating strategy. Pavol Prokop, Jana Švancárová. Personality and Individual Differences, Volume 152, 1 January 2020, 109558. https://doi.org/10.1016/j.paid.2019.109558

Highlights
•    Preference for high heels correlated with female self-perceived attractiveness.
•    Shorter body height correlated with preferences for high heels.
•    High heels were most preferred in interaction with an attractive male.
•    High heels were least preferred in interaction with an unattractive male.
•    High heels are female sexual signals.

Abstract: Females use various behavioural tactics in order to attract the attention of a desirable mate. Wearing high heels enhances female physical attractiveness for the opposite sex, thus their use seems to be a powerful sexual signal. We investigated female preferences for high heels both in everyday life as well as in a hypothetical mating scenario. Slovak females reported a low frequency of wearing high heels (45% once per month, 38% never) in everyday life. Females with a lower body height and high self-perceived attractiveness reported more frequent use of high heels than others. Sociosexuality and involvement in a romantic relationship did not predict the wearing of high heels. When females imagined an interaction with an attractive male, preferences for high heels steeply increased compared with a scenario with an unattractive male. Females with a low body height use high heels in all probability to visually elongate their leg length in order to increase their physical attractiveness. High heels seem to be a form of sexual signalling by females in intersexual interactions.

German first names: Most of the top-rated names on intelligence, competence, and religiousness were male, whereas all top-rated names on attractiveness and warmth were female

Perceived Biological and Social Characteristics of a Representative Set of German First Names. Tillmann Nett et al. Social Psychology, August 20, 2019. https://doi.org/10.1027/1864-9335/a000383

Abstract. We provide ratings for a representative set of 2,000 German first names with regard to perceived sex, foreign origin (yes/no), and familiarity. In two studies participants (N = 736 and N = 237) estimated intelligence, education, attractiveness, religiousness, age, warmth, and competence of persons with the respective name. Descriptive results show strong stereotypes in society in that most of the top-rated names on intelligence, competence, and religiousness were male, whereas all top-rated names on attractiveness and warmth were female. The reliability of most ratings is satisfactory. We provide correlations between the rated dimensions to give an overview of the internal structure of the dataset. To enhance usage of the dataset, we provide an R-package, which allows querying subsets of names depending on experimental requirements.

Keywords: first names, word norms, social perception, stereotypes, German language

Gender differences in spatial navigation: Characterizing wayfinding behaviors

Gender differences in spatial navigation: Characterizing wayfinding behaviors. Ascher K. Munion et al. Psychonomic Bulletin & Review, August 20 2019. https://link.springer.com/article/10.3758/s13423-019-01659-w

Abstract: Men show a consistent spatial navigation advantage over women, which is often attributed to their increased use of survey spatial strategies. But what about men’s navigation gives them an advantage? One possibility is that the way in which men explore environments is fundamentally different, leading to better navigational performance. To test this possibility, this study investigated whether there are gender differences in wayfinding behaviors during navigation that relate to navigational success in a real-world, large-scale, unconstrained navigation task. West Point cadets were given a masked GPS tracker and sent into a large-scale, natural environment to locate targets indicated on maps. We assessed how they explored the environment by computing three measures from the GPS tracks and related these measures to their ability to find the assigned target locations. We also tested whether their self-reported spatial ability related to navigational success. Results showed that males performed better than females, which replicates prior work. Further, traveling longer distances without changing course, pausing less, and fewer returns to previously visited locations were significantly related to the ability to locate the correct target. Consistent with full mediation, the significant relationship between gender and navigational success is fully accounted for by men and women producing different wayfinding behaviors, which in turn predict differences in navigational success. Further, there was no unique relationship between self-reported spatial skills and navigational success. This study is a first step toward showing the relationship between gender, wayfinding behaviors, and navigational success in a natural, real-world navigation task.

Keywords: Navigation Gender differences Wayfinding Spatial cognition

Mock rape trials: Participants perceived the Christian victim as more moral than the atheist victim, which predicted a higher conviction rate

Brown-Iannuzzi, J. L., Golding, J. M., Gervais, W. M., Lynch, K. R., Wasarhaley, N. E., & Bainter, S. (2019). Will jurors believe nonbelievers? Perceptions of atheist rape victims in the courtroom. Psychology of Religion and Spirituality, http://dx.doi.org/10.1037/rel0000278

Abstract: We investigated the impact of a victim’s belief in God on mock jurors’ perceptions of the victim and verdict decisions in a mock rape trial. Four hundred eighteen community members (246 women, 172 men) read a rape trial summary involving an acquaintance rape in which the victim indirectly indicated that she was an atheist, Christian, or there was no mention of religious affiliation. In addition to rendering a verdict, participants rated the victim on her level of morality and rated other aspects of the trial (e.g., victim credibility). We found that the perceived morality of the victim mediated the relationship between the victim’s religious belief and the participants’ verdict, such that participants perceived the Christian victim as more moral than the atheist victim, which predicted a higher conviction rate. In addition, we found evidence for a sequential mediation pattern such that the effect of the victim’s religious belief on participants’ verdict was sequentially mediated by morality, sympathy, credibility, responsibility, and the strength of the prosecution’s case. The results support prior research suggesting atheists are viewed as amoral and have implications for better understanding the role of victim characteristics on attributions in a rape trial.

People increasingly self-segregate into politically homogenous communities; how is unclear; proposal is that people use ambient cues correlated with political values to infer whether they would like to live in those communities

Motyl, Matt, JP Prims, and Ravi Iyer. 2019. “How Ambient Cues Facilitate Political Segregation.” PsyArXiv. August 20. doi:10.31234/osf.io/47zwv

Abstract: People increasingly self-segregating into politically homogenous communities. How they do this remains unclear. We propose that people use ambient cues correlated with political values to infer whether they would like to live in those communities. We test this hypothesis in 5 studies. In Studies 1 (N = 3543) and 2 (N = 5609), participants rated community cues; liberals and conservatives’ preferences differed. In Studies 3a (N = 1643) and 3b (N = 1840), participants read about communities with liberal or conservative cues. Even without explicit information about the communities’ politics, participants preferred communities with politically-congenial cues. In Study 4 (N = 282), participants preferred politically-congenial communities, and wanted to leave politically-uncongenial communities. In Study 5 (N = 370), people selectively navigated their communities in a politically-congenial way. These studies suggest that peoples’ perceptions of communities can be shaped by subtle, not necessarily political, cues that may facilitate growing political segregation.

Tuesday, August 20, 2019

Predictive processing shows how seemingly pointless actions like fidgeting in fact can serve an uncertainty-reducing function; this proposal is extended to autistic stimming, which can be understood as a form of fidgeting

Fidgeting as self-evidencing: A predictive processing account of non-goal-directed action. Kelsey Perrykkad, Jakob Hohwy. New Ideas in Psychology, Volume 56, January 2020, 100750. https://doi.org/10.1016/j.newideapsych.2019.100750

Highlights
•    Predictive processing shows how seemingly pointless actions like fidgeting in fact can serve an uncertainty-reducing function.
•    To resolve mounting uncertainty about the world, agents perform simple and precise actions, confirming their self-model.
•    This proposal is extended to autistic stimming, which can be understood as a form of fidgeting.

Abstract: Non-goal-directed actions have been relatively neglected in cognitive science, but are ubiquitous and related to important cognitive functions. Fidgeting is seemingly one subtype of non-goal-directed action which is ripe for a functional account. What's the point of fidgeting? The predictive processing framework is a parsimonious account of brain function which says the brain aims to minimise the difference between expected and actual states of the world and itself, that is, minimise prediction error. This framework situates action selection in terms of active inference for expected states. However, seemingly aimless, idle actions, such as fidgeting, are a challenge to such theories. When our actions are not obviously goal-achieving, how can a predictive processing framework explain why we regularly do them anyway? Here, we argue that in a predictive processing framework, evidence for the agent's own existence is consolidated by self-stimulation or fidgeting. Endogenous, repetitive actions reduce uncertainty about the system's own states, and thus help continuously maintain expected rates of prediction error minimisation. We extend this explanation to clinically distinctive self-stimulation, such as in Autism Spectrum Conditions, in which effective strategies for self-evidencing may be different to the neurotypical case.

Being politically incorrect makes communicators appear more authentic—specifically, less susceptible to external influence—albeit also less warm

Rosenblum, M., Schroeder, J., & Gino, F. (2019). Tell it like it is: When politically incorrect language promotes authenticity. Journal of Personality and Social Psychology, http://dx.doi.org/10.1037/pspi0000206

Abstract: When a person’s language appears to be political—such as being politically correct or incorrect—it can influence fundamental impressions of him or her. Political correctness is “using language or behavior to seem sensitive to others’ feelings, especially those others who seem socially disadvantaged.” One pilot study, 6 experiments, and 3 supplemental experiments (N = 4,956) demonstrate that being politically incorrect makes communicators appear more authentic—specifically, less susceptible to external influence—albeit also less warm. These effects, however, are moderated by perceivers’ political ideology and how sympathetic perceivers feel toward the target group being labeled politically correctly. In Experiments 1, 2, and 3 using politically incorrect language (e.g., calling undocumented immigrants illegals) made a communicator appear particularly authentic among conservative perceivers but particularly cold among liberal perceivers. However, in Experiment 4 these effects reversed when conservatives felt sympathetic toward the group that was being labeled politically correctly or incorrectly (e.g., calling poor Whites white trash). Experiment 5 tests why political incorrectness can boost authenticity, demonstrating that it makes communicators seem less strategic. Finally, Experiment 6 examines the use of political language in a meaningful field context: perceived persuasion in real political debates. Debaters instructed to be politically correct (vs. politically incorrect) were judged by their uninstructed conversation partners to be easier to persuade during the conversation, although they actually reported being similarly persuaded. Together, these findings demonstrate when and how using politically incorrect language can enhance a person’s authenticity.

Near-accidents with cars were associated with a decrease in the safe driving... In some way, we take a near-accident as a success, and irresponsible behavior increases

Lessons learned from accident and near-accident experiences in traffic. Jens Andreas Terum, Frode Svartdal. Safety Science, Volume 120, December 2019, Pages 672-678. https://doi.org/10.1016/j.ssci.2019.07.040

Highlights
•    Accidents were not associated with safe driving.
•    Near-accidents were associated with a decrease in the safe driving.
•    Learned caution is associated with assuming personal responsibility.

Abstract: The focus of this article is risky behavior in traffic. What do people learn from accidents and near-accidents? Experience with accidents may demand increased caution. However, near-accidents are inherently ambiguous: On the one hand, they signal that margins were good enough, inspiring increased risk-taking; on the other hand, they signal danger that could induce increased caution. To explore these issues, participants (N = 614) answered 47 questions related to safe traffic behavior as well as reported on their experiences with traffic accidents and near-accidents, assessing changes in cautiousness as well as cognitive (i.e., counterfactual thinking) and emotional mechanisms possibly involved in learning from such experience. Results indicate that people do not become more cautious after accidents, whereas repeated experiences with near-accidents seem to foster less cautious traffic behavior. We discuss emotional and cognitive mechanisms related to these effects, and suggest that cautiousness after near-accidents is associated with assuming personal responsibility and upward counterfactual comparisons. We conclude that the mechanisms involved in learning from near-accidents are theoretically interesting, as well as important for the understanding of safe driving behavior.

Women prioritizing career (over family) predicted greater similarity in mate preferences: Placed less importance on men’s parenting qualities, more importance on their access to financial resources, & preferred a career-oriented man

Breadwinner Seeks Bottle Warmer: How Women’s Future Aspirations and Expectations Predict Their Current Mate Preferences. Alyssa Croft et al. Sex Roles, August 14 2019. https://link.springer.com/article/10.1007/s11199-019-01080-6

Abstract: Contemporary women in Western cultures are often trying to juggle careers alongside personal and societal expectations for childrearing in an effort to “have it all.” We examine the effects of this balancing act on heterosexual women’s mate selection motivations. Across three Canadian samples (n = 360), we tested concurrent hypotheses about the desirability of both similar and complementary characteristics in a potential mate. Specifically, women’s aspirations (to prioritize career over family) and their expectations for the roles they will most likely adopt within their future partnerships (primary breadwinner and/or caregiver) were tested as key predictors of mate preferences. Although specific effects varied across samples, a mega-analysis of the combined sample and an internal meta-analysis of effect sizes from the three studies provided support for both complementary and similarity motives (controlling for gender role attitudes). Women’s aspirations to prioritize career (over family) predicted greater similarity in mate preferences, such that they placed less importance on men’s parenting qualities, more importance on their access to financial resources, and preferred a career-oriented over family-oriented exemplar. However, women’s expectations of actually taking on the breadwinner role predicted greater complementarity in mate preferences (greater desirability of parenting qualities and a family-oriented partner; with financial resources rated as less important). Our work expands current understanding of women’s decision-making processes when selecting a mate and has implications for men’s changing traits and roles.

Keywords: Gender roles Mate preferences Communal Agentic Expectations Aspirations

You are not as Cute as you Think you are: Emotional Responses to Expectancy Violations in Heterosexual Online Dating Interaction

You are not as Cute as you Think you are: Emotional Responses to Expectancy Violations in Heterosexual Online Dating Interactions. Maria DelGreco, Amanda Denes. Sex Roles, August 14 2019. https://link.springer.com/article/10.1007/s11199-019-01078-0

Abstract: Dating initiation is a challenging phase of heterosexual romantic relationship development, with men and women often having different expectations and interpretations of communicative cues. With online dating becoming increasingly popular, the challenges of relationship initiation are more apparent and may even lead to negative interpersonal interactions, such as online harassment. The present investigation employed expectancy violations theory to understand and explain perceptions of women’s responses to compliments in an online dating context. We predicted that due to general as well as gender-specific expectations for compliments and responses, when such expectations are violated, conflict and emotional reactions would arise. Using a sample of 413 U.S. undergraduate students, results indicated that women who negatively violate expectations by responding to a compliment using self-praise and agreement were generally evaluated more negatively than women who violated expectations in a positive way by disagreeing with the compliment and women who conformed to expectations by responding with “thank you.” Additionally, results showed that women who positively violated expectations were evaluated more negatively compared to women who conformed to expectations. Implications for expectancy violations theory and power in gendered online interactions are discussed.

Keywords: Online dating Compliments Expectancy violations theory Sexual harassment

Dopamine neurons encode reward prediction errors, used to update value predictions; the delivery of rewards is increased after a costly action, easing more rapid learning under high cost situation

The cost of obtaining rewards enhances the reward prediction error signal of midbrain dopamine neurons. Shingo Tanaka, John P. O’Doherty & Masamichi Sakagami. Nature Communications, volume 10, Article number: 3674 (2019). August 15 2019. https://www.nature.com/articles/s41467-019-11334-2

Abstract: Midbrain dopamine neurons are known to encode reward prediction errors (RPE) used to update value predictions. Here, we examine whether RPE signals coded by midbrain dopamine neurons are modulated by the cost paid to obtain rewards, by recording from dopamine neurons in awake behaving monkeys during performance of an effortful saccade task. Dopamine neuron responses to cues predicting reward and to the delivery of rewards were increased after the performance of a costly action compared to a less costly action, suggesting that RPEs are enhanced following the performance of a costly action. At the behavioral level, stimulus-reward associations are learned faster after performing a costly action compared to a less costly action. Thus, information about action cost is processed in the dopamine reward system in a manner that amplifies the following dopamine RPE signal, which in turn promotes more rapid learning under situations of high cost.

Introduction

Humans and animals prefer a reward received after exerting a lot effort to obtain it compared to the same reward after a smaller amount of effort1,2,3. A number of explanations have been posited for this effect such as effort justification4,5 and the contrast effect6, in which greater value is attributed to an outcome obtained after paid effort. However, it remains unclear whether and how the processing of reward information in the brain is modulated by the effort expended to obtain a reward.

We focused specifically on the midbrain dopamine system, given the role of this system in promoting behavioral adaptation to rewards7,8,9. Dopamine neurons are known to represent reward prediction error (RPE) signals that can facilitate learning of reward predictions by the basal ganglia10,11,12,13,14,15,16,17. The strength of the RPE depends on the quantity, quality, and subjective value or utility of the reward7,18,19,20,21. Moreover, dopaminergic activity is modulated by costs and/or effort22,23. On this basis, we postulated that the dopaminergic RPE signal would be directly modulated by the cost paid to obtain a reward. Furthermore, because the RPE signal is causally involved in mediating learning of stimulus-reward associations24,25,26, we hypothesized that the cost paid to obtain the reward would directly increase the learning speed of stimulus-reward associations.

To test our hypotheses, we measured both behavior and dopaminergic activity in two Japanese monkeys while they performed a saccade based effort task. Monkeys react faster to a reward-predicting cue that is presented after a high-cost (HC) action compared with that after a low-cost (LC) action. The activity of dopaminergic neurons to the reward-predicting cues are increased by the paid cost. In addition, learning speed to the stimulus-reward association is also enhanced by the paid cost. Therefore, we suggest that the cost paid to obtain rewards increases the RPE signal in dopamine neurons and thereby enhances stimulus-reward associations.


Squirrels pilfer each other's nuts at high rates, observing how the others hide the caches; they steal less frequently from relatives

How squirrels protect their caches: Location, conspicuousness during caching, and proximity to kin influence cache lifespan. Mikel Maria Delgado, Lucia F Jacobs. bioRxiv, August 16, 2019. https://doi.org/10.1101/738237

Abstract: Scatter-hoarding animals cannot physically protect individual caches, and instead utilize several behavioral strategies that are hypothesized to offer protection for caches. We validated the use of physically altered, cacheable food items, and determined that intraspecific pilfering among free-ranging fox squirrels (N=23) could be assessed in the field. In this study we were able to identify specific individual squirrels who pilfered or moved caches that had been stored by a conspecific. We identified a high level of pilfering (25%) among this population. In a subsequent study, we assessed the fate of squirrel-made caches. Nineteen fox squirrels cached 294 hazelnuts with passive integrated transponder tags implanted in them. Variables collected included assessment and cache investment and protection behaviors; cache location, substrate, and conspicuousness of each cache; how long each cache remained in its original location, and the location where the cache was finally consumed. We also examined whether assessment or cache protection behaviors were related to the outcomes of buried nuts. Finally, we measured the population dynamics and heterogeneity of squirrels in this study, testing the hypothesis that cache proximity and pilferage tolerance could serve as a form of kin selection. Polymer chain reaction (PCR) was used to analyze hair samples and determine relatedness among 15 squirrels, and the potential impact of relatedness on caching behavior. Results suggested that cache protection behaviors and the lifespan of a cache were dependent on the conspicuousness of a cache. Squirrels may mitigate some of the costs of pilfering by caching closer to the caches of related squirrels than to those of non-related squirrels.

Monday, August 19, 2019

Are Attitudes Contagious? Exposure to Biased Nonverbal Signals Can Create Novel Social Attitudes

Are Attitudes Contagious? Exposure to Biased Nonverbal Signals Can Create Novel Social Attitudes. Allison L. Skinner, Sylvia Perry. Personality and Social Psychology Bulletin, August 19, 2019. https://doi.org/10.1177/0146167219862616

Abstract: Prior work has established that nonverbal signals that capitalize on existing cultural biases can shift attitudes toward members of familiar social groups (e.g., racial minority group members). This research is the first to examine whether nonverbal signals can influence adults’ attitudes toward unfamiliar individuals outside the context of existing cultural biases. In a series of studies, we examined whether seeing one individual receive more cold, unfriendly nonverbal signals than another individual would lead to biases in favor of the target of more positive nonverbal signals. Consistent with our preregistered hypotheses, exposure to nonverbal bias in favor of one individual over another led participants to develop nonverbal signal-consistent explicit biases. Moreover, a combined analysis of the data from all four samples indicated that participants also formed nonverbal signal-consistent implicit biases. Taken together, these findings suggest that nonverbal signals have the potential to create and spread attitudes toward others.

Keywords: nonverbal signals, attitude formation, explicit bias, implicit bias

Watching Television in a Home Environment: Effect on Children’s Attention, Comprehension and Behavior

Rose, Sarah E., Dr, Alexandra Lamont, and Nicholas Reyland. 2019. “Watching Television in a Home Environment: Effect on Children’s Attention, Comprehension and Behavior.” PsyArXiv. August 19. doi:10.31234/osf.io/8yma9

Abstract: Correlational studies have suggested some harmful effects of television (TV) viewing in early childhood, especially for the viewing of fast-paced entertainment programs. However, this has not been consistently supported by experimental studies, many of which have lacked ecological validity.  The current study explores the effects of pace of program on the attention, problem solving and comprehension of 41 3- and 4-year-olds using an ecologically valid experimental design.  Children were visited twice at home; on each visit they were shown an episode of a popular animated entertainment program which differed in pace: one faster paced, one slower paced. Children’s behavior was coded for attention and arousal during viewing, attention, effort and performance after viewing during a problem-solving task, and comprehension of the program. The faster paced program was attended to more, but this had no impact on comprehension. Although 3-year-olds showed more attention and effort on the problem-solving task after watching the slower program, both 3- and 4-year-olds completed more problems successfully after watching the faster program.  The results provide evidence to counter the ‘harm’ perceived in young children watching fast-paced entertainment programs as where differences were found it was the fast-paced program which appeared to have a cognitive facilitation effect.

Preparing for the Worst: Evidence that Older Adults Proactively Downregulate Negative Affect

Preparing for the Worst: Evidence that Older Adults Proactively Downregulate Negative Affect. Brittany Corbett, M Natasha Rajah, Audrey Duarte. Cerebral Cortex, bhz166, August 19 2019, https://doi.org/10.1093/cercor/bhz166

Abstract: Previous studies have only investigated age-related differences in emotional processing and encoding in response to, not in anticipation of, emotional stimuli. In the current study, we investigated age-related differences in the impact of emotional anticipation on affective responses and episodic memory for emotional images. Young and older adults were scanned while encoding negative and neutral images preceded by cues that were either valid or invalid predictors of image valence. Participants were asked to rate the emotional intensity of the images and to complete a recognition task. Using multivariate behavioral partial least squares (PLS) analysis, we found that greater anticipatory recruitment of the amygdala, ventromedial prefrontal cortex (vmPFC), and hippocampus in older adults predicted reduced memory for negative than neutral images and the opposite for young adults. Seed PLS analysis further showed that following negative cues older adults, but not young adults, exhibited greater activation of vmPFC, reduced activation of amygdala, and worse memory for negative compared with neutral images. To the best of our knowledge, this is the first study to provide evidence that the “positivity effect” seen in older adults’ memory performance may be related to the spontaneous emotional suppression of negative affect in anticipation of, not just in response to, negative stimuli.

Keywords: aging, fMRI, memory, spontaneous emotional regulation, uncertainty


Untangling Intelligence, Psychopathy, Antisocial Personality Disorder, and Conduct Problems

Untangling Intelligence, Psychopathy, Antisocial Personality Disorder, and Conduct Problems: A Meta‐analytic Review. Olga Sánchez de Ribera, Nicholas Kavish, Ian M. Katz, Brian B. Boutwell. European Journal of Personality, August 18 2019. https://doi.org/10.1002/per.2207

Abstract: Substantial research has investigated the association between intelligence and psychopathic traits. The findings to date have been inconsistent and have not always considered the multidimensional nature of psychopathic traits. Moreover, there has been a tendency to confuse psychopathy with other closely related, clinically significant disorders. The current study represents a meta‐analysis conducted to evaluate the direction and magnitude of the association of intelligence with global psychopathy, as well as its factors and facets, and related disorders (i.e. antisocial personality disorder, conduct disorder, and oppositional defiant disorder). Our analyses revealed a small, significant, negative relationship between intelligence and total psychopathy (r = −.07, p = .001). Analysis of factors and facets found differential associations, including both significant positive (e.g. interpersonal facet) and negative (e.g. affective facet) associations, further affirming that psychopathy is a multidimensional construct. Additionally, intelligence was negatively associated with antisocial personality disorder (r = −.13, p = .001) and conduct disorder (r = −.11, p = .001) but positively with oppositional defiant disorder (r = .06, p = .001). There was significant heterogeneity across studies for most effects, but the results of moderator analyses were inconsistent. Finally, bias analyses did not find significant evidence for publication bias or outsized effects of outliers

When an intervention to raise intelligence ends, effects fade away; recursive processes between IQ & the environment are not as strong as once thought; intelligence adapts to environmental demands, both upwards & downwards

The environment in raising early intelligence: A meta-analysis of the fadeout effect. John Protzko. Intelligence, Volume 53, November–December 2015, Pages 202-210. https://doi.org/10.1016/j.intell.2015.10.006

Highlights
•    We meta-analyze 39 RCTs that raised children's IQ and followed them after the study ended.
•    We confirm that after an intervention that raises intelligence ends, the effects fade away.
•    The fadeout effect occurs because those in the experimental group lose their IQ advantage.
•    This suggests that recursive processes between IQ and the environment are not as strong as once thought.
•    We propose that intelligence adapts to environmental demands, both upwards and downwards.

Abstract: Many theories about the role of the environment in raising IQ have been put forward. There has not been an equal effort, however, in experimentally testing these theories. In this paper, we test whether the role of the environment in raising IQ is bidirectional/reciprocal. We meta-analyze the evidence for the fadeout effect of IQ, determining whether interventions that raise IQ have sustained effects after they end. We analyze 7584 participants across 39 randomized controlled trials, using a mixed-effects analysis with growth curve modeling. We confirm that after an intervention raises intelligence the effects fade away. We further show this is because children in the experimental group lose their IQ advantage and not because those in the control groups catch up. These findings are inconsistent with a bidirectional/reciprocal model of interaction. We discuss explanations for the fadeout effect and posit a unidirectional–reactive model for the role of the environment in the development of intelligence.

Correlation in intelligence of virtual twins, same-age unrelated siblings raised together from early infancy, drops to zero in adulhood; correlation in real twins is high, consistent with genetic roots

Fullerton Virtual Twin Project: Overview and 2019 Update. Nancy L. Segal & Francisca J. Niculae. Twin Research and Human Genetics, July 29 2019. https://doi.org/10.1017/thg.2019.40

Abstract: Virtual twins (VTs) are defined as same-age unrelated siblings raised together from early infancy. This special class of adoptive siblings replays the rearing situation of twins, absent genetic relatedness. The first such pair was identified and studied in 1990 at the University of Minnesota, leading to the creation of the Fullerton Virtual Twin Study (FVTS) at California State University, Fullerton (CSUF) the following year. The registry currently includes 169 VT pairs, mostly children, with new pairs identified on a regular basis. These sibling sets provide a direct estimate of environmental influences on developmental traits and, as such, offer informative comparisons with ordinary monozygotic and dizygotic twins, full siblings and adoptive brothers and sisters. The sample characteristics, assessment battery and findings to date are summarized in this 2019 update.

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Correlation in intelligence of virtual twins, same-age unrelated siblings raised together from early infancy, drops to zero in adulhood; correlation in real twins is high, consistent with genetic roots

I don't buy that there is "strong support" for a significant "increased" risk of children & adolescents who commit animal cruelty to perpetrate interpersonal violence against humans

Childhood and adolescent animal cruelty and subsequent interpersonal violence in adulthood: A review of the literature. Heng Choon Chan (Oliver), Rebecca W. Y. Wong. Aggression and Violent Behavior, August 19 2019. https://doi.org/10.1016/j.avb.2019.08.007

Abstract: Animal cruelty has been a growing concern worldwide, and is broadly defined as all socially unacceptable behaviors that are intentionally perpetrated to cause unnecessary pain, suffering, distress, and/or death to an animal. This review synthesizes more than 87 research studies identified through online databases and manual search of specific studies. Findings denote that beating, hitting, or kicking, shooting, strangling or smothering, stabbing, and sexual abusing are reported to be the commonly used methods in abusing animals. In addition, children and adolescents abused animals for different reasons; and those who exposed to domestic violence are likely to have higher rates of animal cruelty, which in turn increases their subsequent propensity to engage in delinquent behavior. Male children and adolescents are more likely than their female counterparts to commit acts of animal cruelty. It is noteworthy that early onset of animal cruelty acts is suggested to be predictive of subsequent violent or antisocial behavior. Arguably, bestiality is an act of animal abuse, or specifically as interspecies sexual abuse. More importantly, this review has noted a strong support for the increased risk of children and adolescents who commit animal cruelty to perpetrate interpersonal violence against human victims in later life. Five key theoretical models (i.e., social learning theory, frustration theory, deviance generalization hypothesis, graduation hypothesis, and sexual polymorphous theory) are discussed to explain the link between childhood and/or adolescent animal cruelty and subsequent violence against human victims in adulthood. Implications for research and future research are discussed.

Fence construction deters migration because the migration costs faced by prospective migrants are sensitive to the particular set of available crossing locations; plus the fence disproportionately deters low-skilled migrants

Fenced Out: Why Rising Migration Costs Matter. Benjamin Feigenberg. American Economic Journal: Applied Economics, Forthcoming. https://www.aeaweb.org/articles?id=10.1257/app.20170231&&from=f

Abstract: This paper estimates the impact of the U.S.-Mexico border fence on U.S.-Mexico migration by exploiting variation in the timing of U.S. government investment in fence construction. Using Mexican household survey data and data I collected on fence construction, I find that construction in a given municipality reduces migration by 29% from that municipality and by 15% from adjacent municipalities. I also find that construction reduces migration from non-border municipalities by 32%. I employ a standard migration selection model to rationalize evidence that the fence disproportionately deters low-skilled migrants. The estimated cost of the fence per migrant deterred is $2,850 USD.

Old abstract: Spending on border enforcement has risen by 240% in the United States in the last decade and the construction of a fence on the U.S.-Mexico border has become a focal point in the debate over the costs and benefits of increased border security. However, whether and by how much the fence actually reduces migration from Mexico to the United States remains an open question. This paper estimates the impact of the fence on migration flows between Mexico and the United States and investigates the mechanisms driving observed impacts. To conduct this analysis, I exploit variation in the timing of U.S. government tactical infrastructure investment in fence construction in the period after the passage of the 2006 Secure Fence Act. Using Mexican household survey data and data I collected on border fence construction, I find that construction in a given municipality reduces migration by 39% from that municipality and by 26% from adjacent municipalities. I also find evidence that fence construction reduces migration rates for residents of non-border states with historically low access to smugglers by 38%. Based on these estimates, I calculate that the implied cost of the fence per migrant deterred is $4,800 USD. My findings suggest that fence construction deters migration because the migration costs faced by prospective migrants are sensitive to the particular set of available crossing locations. I derive a simple migration selection model to test this hypothesis and find that a left-censoring of the migration cost distribution, consistent with the disproportionate elimination of low-cost crossing options, best rationalizes evidence on changing migration patterns.

Opioids and social bonding: Effect of naltrexone on feelings of social connection and ventral striatum activity to close others

Inagaki, T. K., Hazlett, L. I., & Andreescu, C. (2019). Opioids and social bonding: Effect of naltrexone on feelings of social connection and ventral striatum activity to close others. Journal of Experimental Psychology: General; http://dx.doi.org/10.1037/xge0000674

Abstract: Close social bonds are critical to immediate and long-term well-being. However, the neurochemical mechanisms by which we remain connected to our closest loved ones are not well understood. Opioids have long been theorized to contribute to social bonding via their actions on the brain. But feelings of social connection toward one’s own close others and direct comparisons of ventral striatum (VS) activity in response to close others and strangers, a neural correlate of social bonding, have not been explored. Therefore, the current clinical trial examined whether opioids causally affect neural and experiential signatures of social bonding. Eighty participants were administered naltrexone (n = 40), an opioid antagonist that blocks natural opioid processing, or placebo (n = 40) before completing a functional MRI scan where they viewed images of their close others and individuals they had not seen before (i.e., strangers). Feelings of social connection to the close others and physical symptoms commonly experienced when taking naltrexone were also collected. In support of hypotheses, naltrexone (vs. placebo) reduced feelings of social connection toward the close others (e.g., family, friends, romantic partners). Furthermore, naltrexone (vs. placebo) reduced left VS activity in response to images of the same close others, but did not alter left VS activity to strangers. Finally, the positive correlation between feelings of connection and VS activity to close others present in the placebo condition was erased by naltrexone. Effects remained after adjusting for physical symptoms. Together, results lend support to theories suggesting that opioids contribute to social bonding, especially with our closest loved ones.

Sunday, August 18, 2019

An ultra-brief measure of the big-five personality domains implicates “agreeableness” as a risk for all-cause mortality

Brief report: How short is too short? An ultra-brief measure of the big-five personality domains implicates “agreeableness” as a risk for all-cause mortality. Benjamin P Chapman, Ari J Elliot. Journal of Health Psychology, August 3, 2017. https://doi.org/10.1177/1359105317720819

Abstract: Controversy exists over the use of brief Big Five scales in health studies. We investigated links between an ultra-brief measure, the Big Five Inventory-10, and mortality in the General Social Survey. The Agreeableness scale was associated with elevated mortality risk (hazard ratio = 1.26, p = .017). This effect was attributable to the reversed-scored item “Tends to find fault with others,” so that greater fault-finding predicted lower mortality risk. The Conscientiousness scale approached meta-analytic estimates, which were not precise enough for significance. Those seeking Big Five measurement in health studies should be aware that the Big Five Inventory-10 may yield unusual results.

Keywords: all-cause mortality, BFI-10, Big Five personality traits, brief scales, General Social Survey

Beijing's Friendship with Singapore's Lee Kuan Yew, 1954–1965

Love the Tree, Love the Branch: Beijing's Friendship with Lee Kuan Yew, 1954–1965. Philip Hsiaopong Liu. The China Quarterly, August 9 2019, https://doi.org/10.1017/S0305741019000900

Abstract: Chinese national identity has long been considered to have been an obstacle to Singapore's nation-building efforts. This is mainly because China was suspected of using its ethnic links to encourage Singapore's communist rebellions during the 1950s and 1960s as Lee Kuan Yew was working towards establishing the city state. This study reviews Lee's exchanges with Beijing and argues that he gave China the impression that he was building an anticolonial, pro-China nation. Beijing therefore responded positively to Lee's requests for support. Reiterating its overseas Chinese policy to Lee, Beijing sided with him against his political rivals and even acquiesced in his suppression of Chinese-speaking “communists.” In addition, China boosted Lee's position against Tunku Abdul Rahman, supported Singapore's independence and lobbied Indonesia to recognize the territory as a separate state. China thus actually played a helpful role in Singapore's nation building.

Endorsement of relationship rituals is associated with greater romantic relationship satisfaction, and increased commitment to the relationship mediates this positive association

Rituals and Nuptials: Relationship Rituals Predict Relationship Satisfaction. Ximena Garcia-Rada, Ovul Sezer, Michael I. Norton. In European Advances in Consumer Research Volume 11, eds. Maggie Geuens, Mario Pandelaere, and Michel Tuan Pham, Iris. Vermeir, Duluth, MN : Association for Consumer Research, http://www.acrwebsite.org/volumes/1700122/volumes/v11e/E-1

ABSTRACT
Across three studies, we show that endorsement of relationship rituals is associated with greater romantic relationship satisfaction, and that increased commitment to the relationship mediates this positive association. Additionally, we document a critical facet that predicts the psychological impact of relationship rituals: that they are held consensually.

Rituals are pervasive in a myriad of social relationships: from religious gatherings to business meetings, rituals are central to social connection (Durkheim, 1912; Goffman, 1967). In sports, fans may engage in pregame rituals to send good vibes to their teams. In business, group members may develop their ritualistic activities to empower themselves before a long day at work. Whether through weddings or funerals, families also engage in rituals to wish happiness to newlyweds, or to pay their respects to lost ones. We empirically explore the potential benefits of rituals in another important social context: romantic relationships. We propose that couples who enact relationship rituals – from weekly date nights to cooking together to bedroom activities – experience greater relationship satisfaction, in part because commitment to enacting rituals manifests in commitment to the relationship. We test this prediction in three studies that examine the relationship between rituals and relationship satisfaction and find that rituals boost commitment in turn leading to greater relationship satisfaction (Studies 1-3). Additionally, we show that consensual endorsement between partners about their rituals predicts relationship satisfaction (Study 2) and distinguish rituals from routines (Study 3).

In Study 1, we examine whether engaging in relationship rituals is associated with greater relationship satisfaction (N=201; Mage=37.18 years, SD=12.10; 59% male). Participants completed a questionnaire that had two sections: a section asking them to report whether they engaged in a relationship ritual with their current/ most recent partner, and a section with a series of relationship quality measures (investment model scale - Rusbult; Martz & Agnew 1998; gratitude –Algoe et al. 2010; perceived partner responsiveness –Caprariello and Reis 2011; closeness – Aron, Aron, and Smollan 1992). Because asking about rituals could lead participants with relationship rituals to recall positive memories or feel regret if they do not have rituals, we randomly assigned participants to either describe their rituals first and then report relationship satisfaction, or the reverse.

We observe that rituals in romantic relationships are ubiquitous: 57% of participants reported engaging in rituals. More importantly, we find that participants with rituals reported greater relationship satisfaction (M=6.98, SD=1.80) than those without a ritual (M=5.93, SD=2.28; b=1.05, SE=.29, t(199)=3.64, p<.001). There was no effect of order of the sections nor was an effect of type of ritual, suggesting that having a ritual may be more important than the specific form that ritual takes. We also observe that participants with relationship rituals reported having fewer alternatives to the relationship, being more invested, more committed, more grateful, feeling closer to their partner, and perceiving that their partners were more responsive (all ps<.05); all effects hold when controlling for relationship length and marital status and when re-running analyses only with participants who were currently in a romantic relationship. Finally, we find that commitment mediates the relationship between rituals and satisfaction (ab=1.08, SE=.25, CI [.59, 1.59]).

Study 2 was identical to Study 1 with one key difference: we recruited one hundred and eight romantic dyads using Qualtrics panel data (N=216; Mage=56.48 years; SD=13.13; 48% male). We replicate findings from Study 1 and show that individuals who engaged in relationship rituals are more satisfied and that the relationship is mediated by commitment (all analyses involved actor-partner interdependence models: ps<.10). We then analyzed responses within-dyads and assessed partners’ agreement on whether they had a ritual: both members of the dyad reported having a ritual (n=55), both members of the dyad reported not having a ritual (n=33), and members of the dyad disagreed on whether they have a ritual (n=20). We created a score of dyad satisfaction by averaging relationship satisfaction ratings provided by both members; agreement within the dyad had a significant effect on relationship satisfaction (F(2, 105)= 3.97, p=.022). Bonferroni post-hoc tests revealed that couples that reported having a ritual were marginally more satisfied in their relationship (M=8.05, SD=1.23) than couples that reported not having a ritual (M=7.32, SD=2.06, p=.092) or couples that disagreed (M=7.11, SD=1.18, p=.058); the latter two groups did not differ (p>.250). These results suggest that the benefits of relationship rituals emerge only when both members of the couple agree on that ritual.

In Study 3, we investigate differences between relationship rituals and routines and show that rituals are conceptually distinct, and lead to psychologically different outcomes. Participants were asked to report whether they had a relationship ritual and a relationship routine, and after answered the same relationship quality measures (N=404; Mage=37.40 years, SD=11.36; 47% male). We observe that participants engaged in both activities: 74% reported having a relationship ritual and 81% reported having a relationship routine. We replicate our previous findings showing that participants who engage in rituals were more satisfied with their relationship (b=1.24, SE=.22, t(402)=5.76, p<.001), but found only a marginal effect for routines (b=.41, SE=.25, t(402)=1.66, p=.099). We then entered rituals and routines in the same model simultaneously predicting relationship satisfaction and found that rituals were significantly associated greater satisfaction (b=1.22, SE=.22, t(401)=5.51, p<.001) but routines were not (b=.11, SE=.25, t(401)=.44, p=.658).

Taken together, our results suggest that couples that adhere to relationship rituals – are more satisfied. Our work makes several contributions to research on shared experiences and interpersonal rituals. First, our findings contribute to prior research that demonstrates that shared experiences lead to greater satisfaction (Boothby, Clark, & Bargh, 2014), enhance social relationships (Gilovich, Kumar, & Jampol, 2015) and drive more coherent and positive retrospection of experiences (Ramanathan & McGill, 2007). We show that relationship rituals are associated with greater relationship satisfaction, especially when partners agree on their ritual, suggesting that sharing an experience (Belk, 2009; Caprariello & Reis, 2013; Kumar & Gilovich, 2015) is particularly important in making interpersonal rituals an effective social cohesion tool.  Second, we identify the psychological mechanism that underlies the association between relationship rituals and relationship satisfaction by shedding light on the importance of greater commitment in relationships. Relationship rituals are effective because they amplify partners’ commitment to relationships, as with other research suggesting that rituals foster feelings of bonding with group members (Durkheim, 1912; Spoor & Kelly, 2004; Xygalatas et al., 2013).

The effects of likes on public opinion perception and personal opinion

The effects of likes on public opinion perception and personal opinion. Pablo Porten-Cheé, Christiane Eilders. The European Journal of Communication Research, Mar 1 2019, https://doi.org/10.1515/commun-2019-2030

Abstract: Drawing on the spiral of silence theory and heuristic information processing, we contend that individuals use likes as sources for assessing public opinion. We further argue that individuals may even adapt their personal opinions to the tenor reflected in those cues. The assumptions were tested using data from an experiment involving 501 participants, who encountered media items on two issues with or without likes. The findings show that respondents inferred public opinion from the media bias if it was supported by likes, however, only in cases of high levels of fear of social isolation. Respondents further adapted their personal opinion to the media bias if it was supported by likes.

Keywords: likes; public opinion; heuristic processing; online media; media effects

Saturday, August 17, 2019

In many different traits, men exhibit larger variation than women, being more likely to fall in the extremes, with the causes anything but resolved

Studying Sex Differences in Psychosocial Life History Indicators. Lee T. Copping, George B. Richardson. Evolutionary Psychological Science, August 17 2019. https://link.springer.com/article/10.1007/s40806-019-00211-2

Abstract: The last decade has seen rapid growth in the study of human life history strategies, with advances to theory, increasingly sophisticated research designs, and innovative new tools now being at the disposal of researchers. Contemporary evolutionary psychology suggests there should be variation in biological and psychological traits attributable to differences between the sexes. We review theory underpinning sex differences in evolutionarily adaptive behaviors and then outline the developmental stages and behaviors pertinent to life history strategies that could be subject to these differences. We then review contemporary work that has examined sex in relation to these domains and end with recommendations for future research agendas. We conclude that future work needs to consider sex more comprehensively (studying the sexes separately when necessary) when evaluating measures and models designed to tackle important life history research questions.

Keywords: Sex differences Life history theory Psychometrics Measurement models Validity


Emoji use with potential partners is associated with maintaining connection beyond the first date, and more romantic and sexual interactions

Worth a thousand interpersonal words: Emoji as affective signals for relationship-oriented digital communication. Amanda N. Gesselman, Vivian P. Ta, Justin R. Garcia. PLOS August 15, 2019. https://doi.org/10.1371/journal.pone.0221297

Abstract: Computer-mediated communication (CMC) is pervasive in our lives, influencing social interaction including human courtship. To connect with potential partners via CMC, modern relationship-seekers must master faster and shorter methods of communicating self-disclosure and affect. Although CMC can lack crucial sensory information in this context, emojis may provide useful aid. Across two studies, we assessed attitudes toward and frequency of emoji use, and whether signaling affect via emoji use relates to more romantic and sexual opportunities. Our findings suggest that emoji use with potential partners is associated with maintaining connection beyond the first date, and more romantic and sexual interactions over the previous year. This research provides evidence that emojis convey important affective information to potential partners, and are potentially associated with more successful intimate connection. Implications for multiple theoretical models and methodologies are discussed.


Sexual economic theory & the human mating market: Bisexual and pansexual women (but not men) enjoy a 7.3% market premium

Sexual economic theory & the human mating market. Stephen Whyte, Robert C. Brooks & Benno Torgler. Applied Economics, Aug 12 2019. https://doi.org/10.1080/00036846.2019.1650886

ABSTRACT: In this study, we apply economic principles to the heterosexual human mating market using data on the socio-demographics, biology, attractiveness, sexual behaviour, and reproductive history of 3,261 Australian online dating participants. More specifically, by using survey participants attractiveness ratings as a proxy for market value, we are able to quantitatively explore theories of sexual economics (SET), which conceptualizes sexual access as an economic resource supplied by women in the human mating market. Our study tests this theory further by incorporating heterosexual market substitutes (namely, 953 bisexual and pansexual individuals) to more accurately integrate the relevant supply and demand forces impacting market value and the commodity of sexual access. We find not only that bisexual and pansexual women (but not men) enjoy a market premium (7.3% higher; p < 0.001) relative to their heterosexual counterparts, but that, contrary to SET, women’s market value in our sample does not diminish with age. We further find that in line with theory and evidence from evolutionary studies, men with (proxied) resources realize a higher market value (6.1% higher for every increased level of educational attainment; p < 0.001) than those without. In conclusion, SET is just one possible model that seeks to understand the complex multi-dimensionality of modern human sexuality and reproduction through an economics lens. As the internet and online dating now provide a low-cost conduit for human mating market participants, so to can it facilitate further large sample scientific studies of mating market dynamics such as this.

KEYWORDS: Sexual economic theory, market value, attractiveness, mating market, sexual orientation
JEL CLASSIFICATION: D10, J10, D91

The lifetime number of sex partners and sexual satisfaction of young adults: the roles of gender, relationship status, motivation and self-esteem

The lifetime number of sex partners and sexual satisfaction of young adults: the roles of gender, relationship status, motivation and self-esteem. G Jongebloed (2019) Faculty of Social and Behavioural Sciences, Master thesis. Utrecht University. https://dspace.library.uu.nl/handle/1874/382822

Abstract: Due to a cultural shift, the lifetime number of sex partners and sexual satisfaction are growing topics of interest. However, research on the direct association between these factors is rare and inconsistent. The current cross-sectional study aims to examine whether there is an association between the lifetime number of sex partners and being sexually satisfied, with gender, the current relationship status and approach- and avoidance sexual motivations as possible moderators of this association. Furthermore, the role of self-esteem within this relationship is investigated. As part of the study ‘Seks onder je 25e’, a survey was conducted among 9,652 heterosexually identified, sexually active, Dutch 18–24 year-olds (M = 21.07 SD = 1.97). Regression analyses revealed that there was no direct association between the lifetime number of sex partners and sexual satisfaction. Gender and relationship status did moderate the association between the lifetime number of sex partners and sexual satisfaction, but approach- and avoidance motivation and self-esteem did not. There was a negative association for women and a positive association for men between the lifetime number of sex partners and sexual satisfaction. Moreover, in contrast to people with a relationship, single people reported to be more sexually satisfied when having had more sex partners. The results are discussed in light of traditional gender norms.

Keywords: sexual satisfaction; sexual double standard; traditional gender norms; number of sex partners; relationship status; self-esteem; sexual motivation.

Check also Why do women regret casual sex more than men do? Leif Edward Ottesen Kennair et al. Personality and Individual Differences, Volume 127, 1 June 2018, Pages 61–67. https://www.bipartisanalliance.com/2018/02/why-do-women-regret-casual-sex-more.html

And  Majority Rules: Gender Composition and Sexual Norms and Behavior in High Schools. Kristen Harknett & Stephen Cranney. Population Research and Policy Review, August 2017, Pages 469-500, http://www.bipartisanalliance.com/2017/08/majority-rules-gender-composition-and.html

And Sexual regret in US and Norway: Effects of culture and individual differences in religiosity and mating strategy. By Mons Bendixen et al. Personality and Individual Differences, October 1 2017, Pages 246–251, http://www.bipartisanalliance.com/2017/06/sexual-regret-in-us-and-norway-effects.html

Delusional Misidentification of the Mirror Image: Entails neurological, neuropsychological, as well as psychiatric aspects of the sense of self

Delusional Misidentification of the Mirror Image. David M. Roane, Todd E. Feinberg, Taylor A. Liberta. Current Neurology and Neuroscience Reports, August 2019. https://link.springer.com/article/10.1007/s11910-019-0972-5

Abstract

Purpose of Review: Delusional misidentification syndromes (DMS) include conditions in which a false belief about the identity of a person, place, or object occurs in the context of psychiatric or neurological disorders. One form of DMS involves the delusion that the patient’s mirror image is a separate individual. This review of reported cases characterizes the psychiatric, neuropathological, and neuropsychological aspects of DMS for the mirror image. An individual case presentation highlights the patient’s subjective experience. Finally, the impact of this syndrome on the sense of self is considered.

Recent Findings: Mirror DMS is a persistent delusion that occurs in the context of neurological illness. It is associated with right hemisphere impairment and a variety of neuropsychological and neuroimaging abnormalities. This phenomenon contributes to our understanding of a range of neurobehavioral syndromes that can be classified as neuropathologies of the self (NPS).

Summary: DMS for the mirror image is a neurobehavioral syndrome in which the inability to recognize oneself in the mirror entails neurological, neuropsychological, as well as psychiatric aspects of the sense of self.

Keywords: Mirror sign Delusional misidentification Neuropathology of the self

Deceptive Affectionate Messages: Mate Retention Deployed Under the Threat of Partner Infidelity

Deceptive Affectionate Messages: Mate Retention Deployed Under the Threat of Partner Infidelity. Neil R. Caton, Sean M. Horan. Evolutionary Psychology, August 13, 2019. https://doi.org/10.1177/1474704919867902

Abstract: Deceptive affectionate messages (DAMs) have been proposed to act as relational maintenance techniques and, as such, might be part of a greater repertoire of mate retention behaviors. We analyzed data from 1,993 Mechanical Turk participants to examine the relations between DAMs and mate retention, and whether these relations were mediated by the perceived risk of partner infidelity. In line with predictions, frequency of DAMs positively predicted general mate retention and cost-inflicting mate retention through the perceived risk of partner infidelity. In line with our nondirectional prediction, we also found that frequency of DAMs negatively predicted benefit-provisioning mate retention behaviors. In an exploratory mediation analysis of DAMs on benefit-provisioning mate retention via perceived partner infidelity, we surprisingly found that DAMs negatively predicted benefit-provisioning behavior due to the perceived risk of partner infidelity, suggesting that DAMs—but not benefit-provisioning mate retention—are deployed under the threat of partner infidelity. Overall, these findings suggest that DAMs might belong to a greater repertoire of mate retention (especially cost-inflicting) behaviors to thwart the possibility of partner infidelity.

Keywords: deceptive affectionate messages, mate retention, perceived infidelity, deceptive affection, deception, evolutionary psychology, relational maintenance, affection, affectionate communication


Friday, August 16, 2019

Reducing the metabolic rate of walking and running with a versatile, portable exosuit - Summary

Reducing the metabolic rate of walking and running with a versatile, portable exosuit. Jinsoo Kim et al. Science  Aug 16 2019: Vol. 365, Issue 6454, pp. 668-672. DOI: 10.1126/science.aav7536

Lowering locomotion's metabolic cost

Walking and running require different gaits, with each type of motion putting a greater bias on different muscles and joints. Kim et al. developed a soft, fully portable, lightweight exosuit that is able to reduce the metabolic rate for both running and walking by assisting each motion via the hip extension (see the Perspective by Pons). A waist belt holds most of the mass, thus reducing the cost of carrying the suit. By tracking the motion of the user, the suit is able to switch modes between the two types of motion automatically.

Abstract: Walking and running have fundamentally different biomechanics, which makes developing devices that assist both gaits challenging. We show that a portable exosuit that assists hip extension can reduce the metabolic rate of treadmill walking at 1.5 meters per second by 9.3% and that of running at 2.5 meters per second by 4.0% compared with locomotion without the exosuit. These reduction magnitudes are comparable to the effects of taking off 7.4 and 5.7 kilograms during walking and running, respectively, and are in a range that has shown meaningful athletic performance changes. The exosuit automatically switches between actuation profiles for both gaits, on the basis of estimated potential energy fluctuations of the wearer’s center of mass. Single-participant experiments show that it is possible to reduce metabolic rates of different running speeds and uphill walking, further demonstrating the exosuit’s versatility.

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Humans can walk and run to attain a wider speed range. At low speeds, the metabolic rate of walking is lower than that of running, but this tendency is reversed at higher speeds, such that at high speeds the metabolic rate of running is lower than that of walking. The ability to switch between walking and running allows humans to adopt the gait with the lowest metabolic rate at each speed (fig. S1A) (1, 2). Development of robotic assistive devices that can provide benefits for both walking and running is challenging because of the fundamentally different biomechanics of these gaits (3). In walking, the legs function like inverted pendulums to move the center of mass (CoM), and the gravitational potential energy and kinetic energy fluctuate out of phase (4). Running, meanwhile, can be modeled as a spring–mass system (5–7) with in-phase gravitational potential and kinetic energy fluctuations (4). In walking, the greatest internal joint moments occur at the ankle, and the hip and ankle perform approximately the same amount of positive work. In running, the greatest internal joint moments occur at the knee and ankle, and the ankle performs the largest amount of positive work, followed by the hip (8, 9).

Because of these differences, most research laboratories have developed separate assistive devices for walking (10–12) and running (3, 13–15). Robotic assistive devices have been shown to reduce the metabolic rate of walking below normal biological levels by 7 to 21% by assisting the ankle joint and/or the hip joint (11, 12, 16, 17). Early efforts at reducing the metabolic rate of running have shown increases of 27 to 58% compared with running without an exoskeleton (13, 14). These increases occur in part because the metabolic cost of carrying mass (e.g., a robotic assistive device) during running (18) is greater than that during walking (19, 20), and the penalty for carrying mass on the limbs is further amplified due to increased limb acceleration (21, 22). Nasiri et al. developed an unpowered exoskeleton that reduced the metabolic rate of running by 8% by applying an elastic torque at the hip as a function of interthigh angle (23). However, those authors noted that this design may not be effective during walking because it could disrupt the swing phase.

We hypothesize that assisting walking and running requires customized actuation profiles via an interface with low distal mass and minimal restriction of motion during the unassisted portions of the gait cycle. To achieve these design criteria, we use functional apparel to attach the device to the wearer, with cables that generate moments in concert with the combined moment that results from different biological muscles. We previously developed such an exosuit that reduces the metabolic rate of walking by 14.9% by assisting the ankle and hip (16). In the current study, we aimed to develop and test a lightweight, portable exosuit that assists with hip extension and can switch automatically between actuation profiles for walking and running. We chose to assist hip extension because it is important for both gaits (8, 9, 24) and does not require added mass to distal leg segments.

The textile components of the device consist of a waist belt and two thigh wraps (Fig. 1A, fig. S2, and data S1). Subjective testing of the maximum range of motion shows that the exosuit does not restrict the movements required for walking and running (Fig. 1B). Two electrical motors connected to cables via pulleys apply a tensile force between the waist belt and the thigh wraps to generate an external extension moment around the hip joint (movie S1 and data S2) (3). The entire exosuit weighs 5.0 kg, with 91% of the total system mass carried at the waist (table S1). This design approach minimizes the additional metabolic rate penalty when mass is added distally during walking (25) and running (22) (Fig. 1C). We programmed two separate actuation force profiles for walking and running. The timings of the walking profile and the running profile were selected on the basis of the profiles with the highest reduction in metabolic rate for walking (26) and running (27) in prior studies that used nonportable, tethered hip exosuits. The profile from the walking study was originally designed to approximate the biological hip extension moment, whereas the profile from the running study was designed to approximate the optimal profile from a muscle-driven simulation (24). Using these profiles as starting points, they were then slightly tailored to improve controller robustness and comfort through pilot tests. To allow the wearer to switch seamlessly between walking and running, we used an online classification algorithm that functions on the basis of potential energy fluctuations measured by inertial measurement units (IMUs) (Fig. 2, movie S1, and data S3) (3, 28).

[full text, graphs, references at the link above]

First indication that dog caretakers may transfer their racial biases onto their pet dogs; or that the caretakers projected their racial biases & perceived dog stereotypes onto their dogs

Dhont, Kristof and Hodson, Gordon and Loughnan, Steve and Amiot, Catherine E. (2019) Rethinking Human-Animal Relations: The Critical Role of Social Psychology. Group Processes & IntergroupRelations. (In press). https://kar.kent.ac.uk/75493

Abstract: People deeply value theirsocial bonds with companion animals, yet routinely devalue other animals, considering them mere commodities to satisfy human interests and desires. Despite the inherently social and intergroup nature of these complexities, social psychology is long overdue in integrating human-animal relations in its theoretical frameworks. The present body of workbrings together social psychological research advancing ourunderstanding of: 1) the factors shaping our perceptionsand thinkingabout animals as social groups, 2) the complexities involved in valuing (caring) and devaluing (exploiting) animals, and 3) the implications and importance of human-animal relationsfor human intergroup relations. In this article, we surveythe diversity of research paradigms and theoretical frameworks developed within the intergroup relations literature that are relevant, perchance critical,to the study of human-animal relations. Furthermore, we highlight how understanding and rethinking human-animal relations will eventually lead to a more comprehensive understanding of many human intergroup phenomena.

Keywords: human-animal relations; speciesism; prejudice; meat consumption; social identity; social dominance; dehumanization; cognitive dissonance


The results offer further evidence that psychosocial influences in the development of adolescent sexual orientation are weak or non‐existent

A longitudinal birth cohort study of early life conditions, psychosocial factors, and emerging adolescent sexual orientation. Yin Xu, Sam Norton, Qazi Rahman. Developmental Psychobiology, August 4 2019. https://doi.org/10.1002/dev.21894

Abstract: This study tested whether previously reported associations between early life factors and later adolescent sexual orientation could be replicated in another prospective birth cohort, the UK Millennium Cohort Study (MCS). We used data on 9,795 youth from the MCS. Emerging sexual orientation was assessed using measures of sexual attraction to males and females in separate items at 14 years. Factors including birthweight, breastfeeding, sibling composition, parental ages, maternal psychopathology, parent‐child relationship, and contextual risks were separated into three developmental periods: prenatal (n = 5 factors), before 7 years (n = 6 factors), and after 7 years (n = 5 factors). We controlled for handedness as a putative marker of prenatal androgen exposure and the possibility of mischievous responding statistically. Girls with greater maternal psychological distress since age 7 and greater pubertal body mass index were more likely to be nonheterosexual but the effect sizes were very small. Among boys there were no significant associations between any early life conditions and later sexual orientation. However, focusing on effect sizes rather than significance levels, there were small associations between preterm birth and nonheterosexuality. The results offer further evidence that psychosocial influences in the development of adolescent sexual orientation are weak or non‐existent.


Gamification as it is currently operationalized in empirical studies is an effective method for instruction, although factors contributing to successful gamification are still somewhat unresolved, especially for cognitive learning

The Gamification of Learning: a Meta-analysis. Michael Sailer, Lisa Homner. Educational Psychology Review, August 15 2019, https://link.springer.com/article/10.1007/s10648-019-09498-w

Abstract: Ths meta-analysis was conducted to systematically synthesize research findings on effects of gamification on cognitive, motivational, and behavioral learning outcomes. Results from random effects models showed significant small effects of gamification on cognitive (g = .49, 95% CI [0.30, 0.69], k = 19, N = 1686), motivational (g = .36, 95% CI [0.18, 0.54], k = 16, N = 2246), and behavioral learning outcomes (g = .25, 95% CI [0.04, 0.46], k = 9, N = 951). Whereas the effect of gamification on cognitive learning outcomes was stable in a subsplit analysis of studies employing high methodological rigor, effects on motivational and behavioral outcomes were less stable. Given the heterogeneity of effect sizes, moderator analyses were conducted to examine inclusion of game fiction, social interaction, learning arrangement of the comparison group, as well as situational, contextual, and methodological moderators, namely, period of time, research context, randomization, design, and instruments. Inclusion of game fiction and social interaction were significant moderators of the effect of gamification on behavioral learning outcomes. Inclusion of game fiction and combining competition with collaboration were particularly effective within gamification for fostering behavioral learning outcomes. Results of the subsplit analysis indicated that effects of competition augmented with collaboration might also be valid for motivational learning outcomes. The results suggest that gamification as it is currently operationalized in empirical studies is an effective method for instruction, even though factors contributing to successful gamification are still somewhat unresolved, especially for cognitive learning outcomes.

Keywords: Gamification Learning Gamified learning Meta-analysis Cognition Motivation Behavior

Thursday, August 15, 2019

Empirical evidence for a statistically significant 4% gender wage gap among workers, at the project level; female workers propose lower wage bills and are more likely to win the competition for contracts, get higher revenues overall

Gomez Herrera, Estrella and Mueller-Langer, Frank, Is There a Gender Wage Gap in Online Labor Markets? Evidence from Over 250,000 Projects and 2.5 Million Wage Bill Proposals (July 9, 2019). Max Planck Institute for Innovation & Competition Research Paper No. 19-07. SSRN: http://dx.doi.org/10.2139/ssrn.3427012

Abstract: We explore whether there is a gender wage gap in one of the largest EU online labor markets, PeoplePerHour. Our unique dataset consists of 257,111 digitally tradeable tasks of 55,824 hiring employers from 188 countries and 65,010 workers from 173 countries that made more than 2.5 million wage bill proposals in the competition for contracts. Our data allows us to track the complete hiring process from the employers' design of proposed contracts to the competition among workers and the final agreement between employers and successful candidates. Using Heckman and OLS estimation methods we provide empirical evidence for a statistically significant 4% gender wage gap among workers, at the project level. We also find that female workers propose lower wage bills and are more likely to win the competition for contracts. Once we include workers’ wage bill proposals in the regressions, the gender wage gap virtually disappears, i.e., it is statistically insignificant and very small in magnitude (0.3%). Our results also suggest that female workers’ higher winning probabilities associated with lower wage bill proposals lead to higher expected revenues overall. We provide empirical evidence for heterogeneity of the gender wage gap in some of the job categories, all job difficulty levels and some of the worker countries. Finally, for some subsamples we find a statistically significant but very small "reverse" gender wage gap.

Keywords: Gender wage gap, online labor markets, digitally performable projects
JEL Classification: D40; J40

The “unmotivated bias” of overprecision causes partisan hostility; prior literature has focused on motivated reasoning and social identity theory;overprecision increases hostility directly and indirectly

“Unmotivated bias” and partisan hostility: Empirical evidence. Daniel F. Stone. Journal of Behavioral and Experimental Economics, Volume 79, April 2019, Pages 12-26. https://doi.org/10.1016/j.socec.2018.12.009

Highlights
•    I argue that the “unmotivated bias” of overprecision causes partisan hostility.
•    Prior literature has focused on motivated reasoning and social identity theory.
•    I present evidence that overprecision increases hostility directly and indirectly.
•    The direct effects hold fixed ideology, partisanship, and motivated reasoning.
•    The indirect effects are via increasing strength of partisanship.

Abstract: Extreme partisan animosity has been on the rise in the US and is prevalent around the world. This hostility is typically attributed to social group identity, motivated reasoning, or a combination thereof. In this paper, I empirically examine a novel contributing factor: the “unmotivated” cognitive bias of overprecision (overconfidence in precision of beliefs). Overprecision could cause partisan hostility indirectly via inflated confidence in one’s own ideology, partisan identity, or perceptions of social distance between the parties. Overprecision could also cause this hostility directly by causing excessively strong inferences from observed information that is either skewed against the out-party or simply misunderstood. Using a nationally representative sample, I find consistent support for direct effects of overprecision and mixed support for indirect effects. The point estimates imply a one standard deviation increase in a respondent’s overprecision predicts as much as a 0.71 standard deviation decline in relative out-party favorability.

Dollars do not determine detection: Monetary value associated with unexpected objects does not affect the likelihood of inattentional blindness

Dollars do not determine detection: Monetary value associated with unexpected objects does not affect the likelihood of inattentional blindness. Dennis Redlich et al. Quarterly Journal of Experimental Psychology, March 18, 2019. https://doi.org/10.1177/1747021819835148

Abstract: Conscious perception often fails when an object appears unexpectedly and our attention is focused elsewhere (inattentional blindness). Although various factors have been identified that modulate the likelihood of this failure of awareness, it is not clear whether the monetary reward value associated with an object can affect whether or not this object is detected under conditions of inattention. We hypothesised that unexpectedly appearing objects that contain a feature linked to high value, as established via reward learning in a previous task, would subsequently be detected more frequently than objects containing a feature linked to low value. A total of 537 participants first learned the association between a perceptual feature (colour) and subsequent reward values (high, low, or none reward). Afterwards, participants were randomly assigned to a static (Experiment 1) or dynamic (Experiment 2) inattentional blindness task including an unexpected object associated with high, low, or none reward. However, no significant effect of the previously learned value on the subsequent likelihood of detection was observed. We speculate that artificial monetary value, which is known to affect attentional capture, is not strong enough to determine whether or not an object is consciously perceived.

Keywords: Failure of awareness, value-driven attention, inattentional blindness

Assessing the effects of vegetable consumption on the psychological health of healthy adults: a systematic review of prospective research

Assessing the effects of vegetable consumption on the psychological health of healthy adults: a systematic review of prospective research. Nicola-Jayne Tuck, Claire Farrow, Jason M Thomas. The American Journal of Clinical Nutrition, Volume 110, Issue 1, July 2019, Pages 196–211, June 1 2019, https://doi.org/10.1093/ajcn/nqz080

ABSTRACT
Background: To alleviate the immense health and economic burden of mental illness, modifiable targets to promote psychological health are required. Emerging evidence suggests that both fruit and vegetable (F&V) consumption may play an important role. However, the precise contribution of vegetable consumption, which may represent a more potent target than the consumption of fruit, has received little attention.

Objectives: This review aimed to synthesize and evaluate research investigating the effects of vegetable consumption on mental health and psychological well-being in nonclinical, healthy adult populations. We aimed to provide insight into the causal relation between vegetable consumption and these outcomes.

Methods: Only studies with prospective or experimental data were included. The survey of the literature was last implemented on 1 February, 2019.

Results: Ten eligible studies were identified, with a total sample size of n = 33,645, that measured vegetable intake separately from fruit, or combined this with fruit intake. Where studies explored the independent effects of fruit and vegetable consumption on psychological health (n = 3), 2 reported a preferential effect of vegetables (compared with fruit) on psychological well-being, whereas 1 reported a superior effect of fruit intake on odds reduction of symptoms of depression. More broadly, there was evidence that consuming the recommended amount of F&V (and exceeding this) was associated with increased psychological well-being. However, the effects of F&V consumption on mental health symptoms were inconsistent.

Conclusions: Increased F&V consumption has a positive effect on psychological well-being and there appears to be a preferential effect of vegetables (compared with fruit) from the limited data examined. The effect of F&V intake on mental health is less clear and, at present, there are no clear data to support a preferential effect of vegetable intake on mental health outcomes. Hence, additional research is warranted to investigate the influence of vegetables, compared with fruit, on psychological health in order to inform nutrition-based interventions. This review was registered at www.crd.york.ac.uk/prospero as CRD42017072880.

Keywords: systematic review, vegetables, fruit, mental health, psychological well-being

Will Healthy Eating Make You Happier? A Research Synthesis Using an Online Findings Archive

Will Healthy Eating Make You Happier? A Research Synthesis Using an Online Findings Archive. Ruut Veenhoven. Applied Research in Quality of Life, August 14 2019. https://link.springer.com/article/10.1007/s11482-019-09748-7

Abstract: Healthy eating adds to health and thereby contributes to a longer life, but will it also add to a happier life? Some people do not like healthy food, and since we spend a considerable amount of our life eating, healthy eating could make their life less enjoyable. Is there such a trade-off between healthy eating and happiness? Or instead a trade-on, healthy eating adding to happiness? Or do the positive and negative effects balance? If there is an effect of healthy eating on happiness, is that effect similar for everybody? If not, what kind of people profit from healthy eating happiness wise and what kind of people do not? If healthy eating does add to happiness, does it add linearly or is there some optimum for healthy ingredients in one’s diet? I considered the results published in 20 research reports on the relation between nutrition and happiness, which together yielded 47 findings. I reviewed these findings, using a new technique. The findings were entered in an online ‘findings archive’, the World Database of Happiness, each described in a standardized format on a separate ‘findings page’ with a unique internet address. In this paper, I use links to these finding pages and this allows us to summarize the main trends in the findings in a few tabular schemes. Together, the findings provide strong evidence of a causal effect of healthy eating on happiness. Surprisingly, this effect is not fully mediated by better health. This pattern seems to be universal, the available studies show only minor variations across people, times and places. More than three portions of fruits and vegetables per day goes with the most happiness, how many more for what kind of persons is not yet established.

Keywords: Happiness Health behaviour Diet Research synthesis


The Pot Rush: Is Legalized Marijuana A Positive Local Amenity?

The Pot Rush: Is Legalized Marijuana A Positive Local Amenity? Diego Zambiasi  Steven Stillman. Economic Inquiry, August 14 2019. https://doi.org/10.1111/ecin.12832

Abstract: This paper examines the amenity value of legalized marijuana by analyzing the impact of marijuana legalization on migration to Colorado. Colorado is the pioneering state in this area having legalized medical marijuana in 2000 and recreational marijuana in 2012. We test whether potential migrants to Colorado view legalized marijuana as a positive or negative local amenity. We use the synthetic control methodology to examine in‐ and out‐migration to/from Colorado versus migration to/from counterfactual versions of Colorado that have not legalized marijuana. We find strong evidence that potential migrants view legalized marijuana as a positive amenity with in‐migration significantly higher in Colorado compared with synthetic‐Colorado after the writing of the Ogden memo in 2009 that effectively allowed state laws already in place to be activated, and additionally after marijuana was legalized in 2013 for recreational use. When we employ permutation methods to assess the statistical likelihood of our results given our sample, we find that Colorado is a clear and significant outlier. We find no evidence for changes in out‐migration from Colorado suggesting that marijuana legalization did not change the equilibrium for individuals already living in the state.