Tuesday, November 21, 2017

Experimental evidence that female rhesus macaques (Macaca mulatta) perceive variation in male facial masculinity

Experimental evidence that female rhesus macaques (Macaca mulatta) perceive variation in male facial masculinity. Kevin A Rosenfield, Stuart Semple, Alexander V Georgiev, Dario Maestripieri, James P HIgham, Constance Dubuc. BioRxiv, Nov 2017, doi: https://doi.org/10.1101/222810

Abstract: Among many primate species, face shape is sexually dimorphic, and male facial masculinity has been proposed to influence female mate choice and male-male competition. However, whether conspecifics pay attention to facial masculinity has only been assessed in humans. In a study of free-ranging rhesus macaques, Macaca mulatta, we used a two alternative look-time experiment to test whether females perceive male facial masculinity. We presented 107 females with pairs of images of male faces, one with a more masculine shape and one more feminine, and recorded their looking behaviour. Females looked at the masculine face longer than at the feminine face in more trials than predicted by chance. Although there was no overall difference in average look-time between masculine and feminine faces across all trials, females looked significantly longer at masculine faces in a subset of trials for which the within-pair difference in masculinity was most pronounced. Additionally, the proportion of time subjects looked toward the masculine face increased as the within-pair difference in masculinity increased. This study provides evidence that female macaques perceive variation in male facial shape, a necessary condition for intersexual selection to operate on such a trait. It also highlights the potential impact of perceptual thresholds on look-time experiments.

Can the positive effects of inspiration be extended to different domains?

Klein JW, Case TI, Fitness J. Can the positive effects of inspiration be extended to different domains? J Appl Soc Psychol. 2017;00:1–7. https://doi.org/10.1111/jasp.12487

Abstract: It is presently unknown whether inspiration extends across different domains: can a salesperson, for example, be inspired by a successful athlete? The present study investigated whether inspirational content must be relevant to a subsequent task to improve performance. Participants (N = 70) wrote about a time they felt inspired in a sporting context (domain-relevant), creative context (domain-irrelevant); or amused (positive control). Participants then held a handgrip, with the option of giving up or continuing to exhaustion. Regardless of the relevance of the inspirational content to the performance task, inspired participants were less likely to give up than controls. This is the first research to show that the benefits of inspiration reach beyond the domain defined by the inspiring event.

What kind of love is love at first sight? Frequently unrequited.

ZSOK, F., HAUCKE, M., DE WIT, C. Y. and BARELDS, D. P. H. (2017), What kind of love is love at first sight? An empirical investigation. Pers Relationship. doi:10.1111/pere.12218

Abstract: Love at first sight (LAFS) is a commonly known phenomenon, but has barely been investigated scientifically. Major psychological theories of love predict that LAFS is marked by high passion. However, it could also be a memory confabulation construed by couples to enhance their relationship. We investigated LAFS empirically by assessing feelings of love at the moment participants met potential partners for the first time. Data were collected from an online study, a laboratory study, and three dating events. Experiences of LAFS were marked neither by high passion, nor by intimacy, nor by commitment. Physical attraction was highly predictive of reporting LAFS. We therefore suggest that LAFS is not a distinct form of love, but rather a strong initial attraction that some label as LAFS, either in the moment of first sight or retrospectively.

Dreaming contains abundant references from recent dreamer’s own life, following a surprising 7 day U-shaped timescale (most recent and most old memories in the 7-day period)

Eichenlaub JB., Cash S.S., Blagrove M. (2017) Daily Life Experiences in Dreams and Sleep-Dependent Memory Consolidation. In: Axmacher N., Rasch B. (eds) Cognitive Neuroscience of Memory Consolidation. Studies in Neuroscience, Psychology and Behavioral Economics. Springer, https://doi.org/10.1007/978-3-319-45066-7_10

Abstract: Memories constitute much of the source material for our dreams. Although waking life events are not faithfully replayed in dreams, dream content arises from recent daily experiences. Numerous empirical studies and theoretical accounts highlight the key function of sleep in the consolidation of newly learned memories, raising the question how reference to waking memories in dreams relates to ongoing memory-related processes that take place during sleep. This review attempts to present first the current knowledge of the incorporation of waking memories in dreams by highlighting three main features of this phenomenon i.e. (1) dreaming contains abundant references from recent dreamer’s own life, (2) the wake-dream relation can follow a surprising 7 day U-shaped timescale and (3) salient/intense waking events are more easily incorporated than indistinct/less-intense waking events. Second, this review attempts to discuss the relationship between this phenomenon and the memory-related processes that take place during sleep. The features of the incorporation of waking memories in dreams are in line with some characteristics of the memory processing hypothesized to take place during sleep, suggesting that dreaming might reflect this memory processing. However, substantial limitations and alternative hypotheses must be regarded and addressed in future studies to clarify the link between dream content and sleep-dependent memory consolidation.

Off-label treatments were not consistently better or worse than approved drug treatments in randomized trials

Off-label treatments were not consistently better or worse than approved drug treatments in randomized trials. Aviv Ladanie et al. Journal of Clinical Epidemiology, https://doi.org/10.1016/j.jclinepi.2017.11.006


---What is already known
⁃    Off-label drug use is highly prevalent in clinical practice, but its use is controversial and often discouraged
⁃    Lack of regulatory approval nourishes the assumption that off-label drug treatment effects are systematically less favourable compared to approved drug treatments
⁃    However, this assumption has never been empirically assessed using clinical trial evidence

---What this study adds
⁃    Medical effects associated with off-label drug use are highly heterogeneous and do not appear to be systematically inferior when compared to approved drug treatments
⁃    Relying on the approval status of drugs should not replace thorough assessment of benefits and harms on a case by case basis to ensure that patients receive the best available care


Background: Off-label drug use is highly prevalent, but controversial and often discouraged assuming generally inferior medical effects associated with off-label use.

Methods: We searched Medline, PubMed Health and the Cochrane Library up to May 2015 for systematic reviews including meta-analyses of randomized clinical trials (RCTs) comparing off-label and approved drugs head-to-head in any population and on any medical outcome. We combined the comparative effects in meta-analyses providing summary odds ratios (sOR) for each treatment comparison and outcome, and then calculated an overall summary of the sOR across all comparisons (ssOR).

Results: We included 25 treatment comparisons with 153 RCTs and 24 592 patients. In six of 25 comparisons (24%), off-label drugs were significantly superior (five of 25) or inferior (one of 25) to approved treatments. There was substantial statistical heterogeneity across comparisons (I2=43%). Overall, off-label drugs were more favorable than approved treatments (ssOR 0.72; 95% CI=0.54-0.95). Analyses of patient-relevant outcomes were similar (statistical significant differences in 24% (six of 25); ssOR 0.74; 95% CI=0.56-0.98; I2=60%). Analyses of primary outcomes of the systematic reviews (n=22 comparisons) indicated less heterogeneity and no statistically significant difference overall (ssOR 0.85; 95% CI=0.67-1.06; I2=0%).

Conclusions: Approval status does not reliably indicate which drugs are more favorable in situations with clinical trial evidence comparing off-label with approved use. Drug effectiveness assessments without considering off-label use may provide incomplete information. To ensure that patients receive the best available care, funding, policy, reimbursement, and treatment decisions should be evidence based considering the entire spectrum of available therapeutic choices.

Love Influences Reproductive Success in A Traditional Hunter-Gatherer Population

Love Influences Reproductive Success in Humans. Piotr Sorokowski et al. Front. Psychol., 21 November 2017 | https://doi.org/10.3389/fpsyg.2017.01922

Abstract: As love seems to be universal, researchers have attempted to find its biological basis. However, no studies till date have shown its direct association with reproductive success, which is broadly known to be a good measure of fitness. Here, we show links between love, as defined by the Sternberg Triangular Theory of Love, and reproductive success among the Hadza—traditional hunter-gatherer population. We found that commitment and reproductive success were positively and consistently related in both sexes, with number of children showing negative and positive associations with intimacy and passion, respectively, only among women. Our study may shed new light on the meaning of love in humans' evolutionary past, especially in traditional hunter-gatherer societies in which individuals, not their parents, were responsible for partner choice. We suggest that passion and commitment may be the key factors that increase fitness, and therefore, that selection promoted love in human evolution. However, further studies in this area are recommended.

Envy (pity) could involve misperceiving that envied (pitied) others have lives that are uniformly wonderful (awful)

(Mis)imagining the good life and the bad life: Envy and pity as a function of the focusing illusion. Ed O'Brien et al. Journal of Experimental Social Psychology, Volume 75, March 2018, Pages 41–53. https://doi.org/10.1016/j.jesp.2017.10.002

•    People often overweight salient features and neglect small nuances of judgment targets.
•    This “focalism” was applied to better understanding why people feel envy and pity.
•    People neglect everyday ups and downs of envied others, (wrongly) assuming life is uniformly good.
•    People neglect everyday ups and downs of pitied others, (wrongly) assuming life is uniformly bad.
•    These inflated emotional reactions can be reduced by some, not all, defocusing tasks.

Abstract: Envy is a negative state arising when we encounter others with more desirable circumstances than our own. Its converse is pity, a negative state elicited by downward comparisons towards worse-off others. Both classes of emotions first require us to infer what a person's life as a whole must be like. However, the “focusing illusion” suggests these impressions of others are incomplete: we may overweight extreme features (the exceptionally good circumstances of envied others and exceptionally bad circumstances of pitied others) at the cost of overlooking the smaller ups and downs of daily life, which inevitably dilute the other person's overall experience. If so, envy and pity could involve misperceiving that envied others have lives that are uniformly wonderful (overlooking that they still face smaller annoyances) and pitied others have lives that are uniformly awful (overlooking that they still enjoy smaller pleasures). Five studies support this possibility. First, participants evaluated different peers. Consistent with focalism, the more envy and pity they felt, the more disparities they perceived (Study 1)—yet the actual everyday lives of envied and pitied others were similar (Study 2). Participants then completed various defocusing tasks designed to bring to mind others' smaller ups and downs. This indeed reduced envy and pity (Studies 3–4a–4b–5), but pity proved harder to reduce (Studies 4b–5). These studies suggest the same underlying focalism may inflate feelings of envy and pity, with asymmetric regulation strategies: small annoyances spoil perceptions of a good life more than small pleasures enhance perceptions of a bad life.

Keywords: Social judgment; Focalism; Everyday life

About the girls... Alcohol does not influence the selection of short-term partners with dark triad traits

A drunk heart speaks a sober mind: Alcohol does not influence the selection of short-term partners with dark triad traits. Gayle Brewer, Paul Christiansen, Diana Dorozkinaite, Beth Ingleby, Lauren O'Hagan, Charlotte Williams, Minna Lyons. Personality and Individual Differences, https://doi.org/10.1016/j.paid.2017.11.028

•    Women were averse to high dark triad faces.
•    Women perceived men high on dark triad traits as dangerous.
•    Alcohol consumption did not influence ratings of facial composites.

Abstract: Previous research has found that women dislike facial morphs of high dark triad (i.e., psychopathic, Machiavellian, and narcissistic) men. In this study, we tested the influence of alcohol on mate choice and perceptions of danger in dark triad faces. Women (N = 96) were randomly allocated to one of three conditions: control; alcohol; or placebo. In two alternative forced-choice (2-AFC) tasks, participants were first asked to choose between high and low morphs as short-term partners, and then to identify the face they found more dangerous. Analyses indicate that women were averse to male faces with high levels of psychopathy, Machiavellianism, and narcissism for short-term relationships. Women also perceived men whose faces displayed high levels of psychopathy, Machiavellianism, and narcissism to be dangerous. Preference for short-term partners with high or low levels of each dark triad trait and perceived danger did not differ across the experimental conditions. Findings are consistent with previous research indicating that women dislike male faces high on dark triad traits. Findings further suggest that faces high on each dark triad trait are perceived to be dangerous and perceptions of dark triad traits are not influenced by alcohol consumption.

Keywords: Alcohol; Dark triad; Facial preference; Machiavellianism; Narcissism; Psychopathy; Threat

Synthetic Copulin Does Not Affect Men’s Sexual Behavior

Synthetic Copulin Does Not Affect Men’s Sexual Behavior. Megan N. Williams, Coren Apicella. Adaptive Human Behavior and Physiology, https://link.springer.com/article/10.1007/s40750-017-0083-y

Abstract: Chemical communication plays an important role in the social interactions and mating behavior of diverse animal taxa; yet its role in humans remains equivocal. Using a randomized, placebo-controlled experiment involving 243 male participants, we test whether exposure to synthetic copulin – a mixture of volatile fatty acids secreted vaginally in primates, increases 1) men’s sexual motivation using an incentivized behavioral task, 2) self-reported willingness to take sexual risks, 3) preference for short-term mating, 4) perceptions of female attractiveness and 5) self-reported mate value. Because chemical receptors are found throughout the body and human chemosensory pathways have yet to be definitively identified, we also manipulate the location of copulin exposure (i.e. olfactory epithelium versus epidermal keratinocytes in the genital region). Finally, we examine whether prior sexual experience mediate any behavioral effects. Unlike previous reports, we fail to find any effects of copulin exposure on measures of men’s sexual behavior.