Thursday, October 25, 2018

Rolf Degen summarizing: Across cultures, women agreed about which male faces signalled a penchant for sexual unfaithfulness, but actual hit rate was low, indicating that potential cheaters evolved to hide their true nature

Impressions of sexual unfaithfulness and their accuracy show a degree of universality. Clare A. M. Sutherland et al. PLOS One, https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0205716

Abstract: Forming accurate impressions of others’ trustworthiness is a critical social skill, with faithfulness representing a key aspect of trust in sexual relationships. Interestingly, there is evidence for a small degree of accuracy in facial impressions of sexual unfaithfulness. Theoretical accounts suggest that these impressions may function to help with partner selection, and may be universal. If so, impressions should be similar for perceivers from different cultures and accuracy should not be limited to own-race faces. We tested these predictions by asking Caucasian and Asian women to judge the likelihood of unfaithfulness from the faces of Caucasian males whose past sexual history was known. In two studies we found high cross-cultural agreement in these impressions, consistent with universality in the impressions themselves. In Study 1, we found an other-race effect in impression accuracy, with significantly less accurate cross-race impressions by Asian women than own-race impressions by Caucasian women. Asian women showed no accuracy. Interestingly, in Study 2, Asian women who had grown up in the West showed small but significant accuracy in their impressions, with no other-race effect. Results are consistent with a degree of universality in the accuracy of this important aspect of social perception, provided that perceivers have experience with the faces being assessed.

Ignorance of History and Perceptions of Racism: Another Look at the Marley Hypothesis

Ignorance of History and Perceptions of Racism: Another Look at the Marley Hypothesis. Jason E. Strickhouser, Ethan Zell, Kara E. Harris. Social Psychological and Personality Science, https://doi.org/10.1177/1948550618808863

Abstract: Why do White Americans perceive less racism than Black Americans? Two provocative studies on the Marley hypothesis suggest that White Americans are more ignorant of historical instances of racism than Black Americans and that ignorance of history mediates racial differences in perceptions of racism. We conducted two replications of the Marley hypothesis in a different institutional and regional context than prior studies. In contrast with prior findings, the difference between White and Black Americans knowledge of historical racism was not significant in either of our replications and was dramatically smaller than that obtained in prior studies. Thus, the present research failed to replicate the mediation effect found in prior studies. We discuss potential explanations for these discrepant findings (e.g., differences in institution and region) and call for additional research examining whether the Marley hypothesis is moderated by cultural contexts.

Keywords: social perception, racism, minority groups, intergroup relations, replication

The activity of midbrain dopamine neurons & mesolimbic dopamine levels are consistently modulated by anticipated future reward more strongly & consistently than effort, even after weighting reward & effort on behavior equally

What Is the Relationship between Dopamine and Effort? Mark E.Walton and Sebastien Bouret. Trends in Neurosciences, https://doi.org/10.1016/j.tins.2018.10.001

Highlights
* Compared to reward, effort remains poorly understood, both at the behavioral and neurophysiological levels.
* Dopamine has been proposed as central to effort-related decision making, but its role is not clearly defined.
* In fact, the activity of midbrain dopamine neurons and mesolimbic dopamine levels are consistently modulated by anticipated future reward more strongly and consistently than effort, even when the weight of reward and effort on behavior are equated.
* These signals may promote decisions to act based on the potential gain from a future reward.

Abstract: The trade-off between reward and effort is at the heart of most behavioral theories, from ecology to economics. Compared to reward, however, effort remains poorly understood, both at the behavioral and neurophysiological levels. This is important because unwillingness to overcome effort to gain reward is a common feature of many neuropsychiatric and neurological disorders. A recent surge in interest in the neurobiological basis of effort has led to seemingly conflicting results regarding the role of dopamine. We argue here that, upon closer examination, there is actually striking consensus across studies: dopamine primarily codes for future reward but is less sensitive to anticipated effort cost. This strong association between dopamine and the incentive effects of rewards places dopamine in a key position to promote reward-directed action.

Competition- & mate-related cues & interactions rapidly increase testosterone; these increases map onto ongoing and future competitive and mate-seeking behaviours; testosterone administration rapidly modulates neural processing & behaviour

Human social neuroendocrinology: Review of the rapid effects of testosterone. Shawn N.Geniole, Justin M.Carré. Hormones and Behavior, Volume 104, August 2018, Pages 192-205. https://doi.org/10.1016/j.yhbeh.2018.06.001

Highlights
•    We review human social neuroendocrinology studies involving testosterone.
•    Competition- and mate-related cues and interactions rapidly increase testosterone.
•    These increases map onto ongoing and future competitive and mate-seeking behaviours.
•    Testosterone administration rapidly modulates neural processing and behaviour.
•    We propose a new, integrative model: the Fitness Model of Testosterone Dynamics.

Abstract: It is well documented that testosterone concentrations change rapidly within reproductively relevant contexts (e.g., competition, mate-seeking). It has been argued that such rapid changes in testosterone may serve to adaptively fine-tune ongoing and/or future social behaviour according to one's social environment. In this paper, we review human correlational and experimental evidence suggesting that testosterone fluctuates rapidly in response to competition and mate-seeking cues, and that such acute changes may serve to modulate ongoing and/or future social behaviours (e.g., risk-taking, competitiveness, mate-seeking, and aggression). Some methodological details, which limit interpretation of some of this human work, are also discussed. We conclude with a new integrative model of testosterone secretion and behaviour, the Fitness Model of Testosterone Dynamics. Although we focus primarily on human aggression in this review, we also highlight research on risk-taking, competitiveness, and mate-seeking behaviour.

The Moral Machine gathered 40 million decisions in ten languages from millions of people in 233 countries: Differences correlate with modern institutions and deep cultural traits

The Moral Machine experiment. Edmond Awad, Sohan Dsouza, Richard Kim, Jonathan Schulz, Joseph Henrich, Azim Shariff, Jean-François Bonnefon & Iyad Rahwan. Nature (2018), https://www.nature.com/articles/s41586-018-0637-6

Abstract: With the rapid development of artificial intelligence have come concerns about how machines will make moral decisions, and the major challenge of quantifying societal expectations about the ethical principles that should guide machine behaviour. To address this challenge, we deployed the Moral Machine, an online experimental platform designed to explore the moral dilemmas faced by autonomous vehicles. This platform gathered 40 million decisions in ten languages from millions of people in 233 countries and territories. Here we describe the results of this experiment. First, we summarize global moral preferences. Second, we document individual variations in preferences, based on respondents’ demographics. Third, we report cross-cultural ethical variation, and uncover three major clusters of countries. Fourth, we show that these differences correlate with modern institutions and deep cultural traits. We discuss how these preferences can contribute to developing global, socially acceptable principles for machine ethics. All data used in this article are publicly available.

Sex & the city. Are financial decisions driven by emotions? Our findings suggest that agents incorrectly attribute their good mood to positive economic perspectives rather than positive emotions

Sex & the city. Are financial decisions driven by emotions? Giampaolo Gabbi, Giovanna Zanotti. Journal of Behavioral and Experimental Finance, https://doi.org/10.1016/j.jbef.2018.10.005

Abstract: Although the role of irrationality in trading choices has been extensively discussed in the literature, individual incidental emotions have been neglected. We investigated emotional explanatory factors and trading choices in a sample of non-professional agents who managed a virtual financial positions pretending to be traders. Using a series of daily surveys over a five-week period as well as introductive inventory surveys, we constructed measures of core affect and emotions and correlated these with subjects’ financial choices. Our purpose is to test if the decision to buy or sell financial assets is affected by the emotional state of individuals, considering also gender clusters. A focus is on incidental emotions, detecting how positive emotions due to sexual activity may alter financial trading choices. Our findings suggest that agents incorrectly attribute their good mood to positive economic perspectives rather than positive emotions.

Rodents' ultrasonic vocalizations are actively produced by both sexes during sexual interactions, contrary to earlier assumptions; male-typical and female-typical vocal behaviors can be identified

Vocal Signals of Sexual Motivation in Male and Female Rodents. Marcela Fernández-Vargas. Current Sexual Health Reports, https://link.springer.com/article/10.1007/s11930-018-0179-9

Abstract

Purpose of the Review: Rodents produce ultrasonic vocalizations (USV) under different social contexts, including courtship and reproduction. The present review aims to summarize the behavioral, bioacoustical, and physiological evidence that USV are reliable signals of sexual motivation in both male and female rodents.

Recent Findings: USV are actively produced by both sexes during sexual interactions, contrary to earlier assumptions. Male-typical and female-typical vocal behaviors can be identified. Calling rates and acoustic parameters, such as call duration, frequency, and energy, can be modulated rapidly over time by motivational state and sexual context. USV produced in response to sexual context could be regulated by the brain on a moment-to-moment basis through non-classical mechanisms of steroid action. Finally, I provide some practical considerations for the acoustic and statistical analyses of these vocal signals.

Summary: USV can be used as signals of sexual motivation in both sexes to study brain and hormonal mechanisms underlying sexual behavior or sexual differentiation.

Keywords: Ultrasonic vocalizations Sexual behavior Sexual motivation Sex steroids Bioacoustics Communication Nongenomic steroid action Rodents House mouse Rats Golden hamsters Syrian hamsters