Wednesday, November 1, 2017

Prenatal androgens apparently have large effects on interests and engagement in gendered activities; moderate effects on spatial abilities; and relatively small or no effects on gender identity, gender cognitions, and gendered peer involvement

Berenbaum, S. A. (2017), Beyond Pink and Blue: The Complexity of Early Androgen Effects on Gender Development. Child Dev Perspect. doi:10.1111/cdep.12261

Abstract: Why do girls and women differ from boys and men? Gender development is typically considered to result from socialization, but sex hormones present during sensitive periods of development, particularly prenatal androgens, play an important role. Data from natural experiments, especially from females with congenital adrenal hyperplasia, show the complexity of the effects of androgens on behavior: Prenatal androgens apparently have large effects on interests and engagement in gendered activities; moderate effects on spatial abilities; and relatively small or no effects on gender identity, gender cognitions, and gendered peer involvement. These differential effects provide an opportunity to move beyond identifying sources of variation in behavior to understanding developmental processes. These processes include links among gendered characteristics, psychological and neural mechanisms underlying development, and the joint effects of biological predispositions and social experiences.

People are reluctant to be dishonest to interaction partners with dilating pupils, which are perceived positively

Pupil to pupil: The effect of a partner's pupil size on (dis)honest behavior. Jolien A. van Breen, Carsten K.W. De Dreu, Mariska E. Kret. Journal of Experimental Social Psychology, Volume 74, January 2018, Pages 231–245.

•    People are reluctant to be dishonest to interaction partners with dilating pupils.
•    Findings suggest that partners with dilating pupils are perceived more positively, resulting in more pro-social treatment.
•    The pro-social effects of dilating pupils were most evident in competitive contexts.
•    Pupil mimicry was restricted to non-competitive contexts.
•    The effect of observed pupil dilation on dishonesty does not rely on the occurrence of pupil mimicry between partners.

Abstract: Being observed by others fosters honest behavior. In this study, we examine a very subtle eye signal that may affect participants' tendency to behave honestly: observed pupil size. For this, we use an experimental task that is known to evoke dishonest behavior. Specifically, participants made private predictions for a coin toss and earned a bonus by reporting correct predictions. Before reporting the (in)correctness of their predictions, participants viewed videos of partners with dilating or constricting pupils. As dilating pupils are generally perceived positively, we expected that dishonesty would be reduced when participants look into the eyes of a partner with dilating pupils, especially when their own pupil size mimics the observed pupil size. In line with this prediction, Experiments 1 and 2 showed that, when earning a bonus meant harming the interaction partner, dishonesty occurred less frequently when the partner's pupils dilated rather than constricted. That is, when the interests of the self and the other conflict, participants use the pupil of the partner as a social cue to inform their behavior. However, pupil mimicry was not observed. In Experiment 3, we examined pupil mimicry and dishonesty in a context where there was no temptation to hurt the partner. Here, pupil mimicry between partners was observed, but there were no effects of the partner's pupil on dishonesty. Thus, when dishonesty harms the interaction partner, participants use pupillary cues from their partner to inform their behavior. Pupil mimicry, however, is bound to non-competitive contexts only.

Keywords: Pupil size; Pupil mimicry; Dishonesty; Interpersonal interaction; Competition

Mate choice could be random in female rats (Rattus norvegicus)

Mate choice could be random in female rats (Rattus norvegicus). Olivia Le Mo├źne, Eelke M. Snoeren. Physiology & Behavior,

•    Female rats prefer the male visited first in a multiple partners paradigm.
•    This mate selection is not based on the male rats, but on the location of the male.
•    It suggests that mate choice in female rats is random.

Abstract: Female mate choice is often investigated in terms of reproductive success in order to understand how male characteristics contribute to sexual attractiveness. Previous studies have found that females rats prefer mating with their first encounter rather than males visited subsequently, suggesting that the rewarding value of this first encounter is enough to reinforce mating with the first partner. Using a multiple chambers paradigm, we allowed female rats to copulate freely with three males placed each in a different chamber. Then, we switched the males' position, and let the female interact with them freely again within the same session. We tested whether female mate choice was relying rather on a preferred male rat or on a preferred mating location. The results showed that females spent most time with the male in the chamber of 1st entry in the beginning, but as soon as male rats switched chambers, the female rat continued to copulate with the new male in the same chamber of 1st entry, instead of mating with her previously preferred male rat. This suggests that the male preference is an artefact of location preference. Therefore, female mate choice seems to be rather random than the consequence of an individual choice based on male characteristics. This finding, although contradictory with the intuitive feeling that mate choice is a crucial feature in sexual and reproductive behavior, is supported by several recent observations. In the coming years, behavioral neuroscience should bring light to the brain processes at work in random mate choice.

Keywords: Female rats; Multiple partner; Sexual behavior; Mate choice; Location

The procedures were similar to those previously described [1]. At the start of the experiment, a (sexually experienced, hormonally primed) female rat was placed in the
middle chamber of the multiple chambers set-up. The subject was allowed to move freely and habituate to the chambers for 5 minutes. Then, for another 5 minutes, the female was placed in the middle chamber, while three (sexually experienced) male rats were positioned in the three surrounding small chambers. During this time, the openings were blocked with a wire mesh allowing the female subject to see, smell and hear the male rats without any possibility of physical contact (habituation phase). The number of times the female rat sniffed the opening of each of the male chambers was determined, as an indicator of olfactory preference [10, 11].

After the habituation phase, the openings were unblocked and the female rat was allowed to move freely between the chambers for another 15 minutes (copulation phase A). During this period, the following behaviors were scored for each male: order in which the males were visited, latency to first visit, number of visits, time spent in the chambers, number of sniff episodes to the openings of the chambers, and the number of mounts, intromissions and ejaculations per male. In addition, the number of paracopulatory behaviors the female performed in the chamber of each male were counted.

After the copulation phase A, the male rats were quickly randomly placed in a different chamber and the test continued for another 15 minutes (copulation phase B). During this period, the same parameters were scored as during copulation phase A. All sessions were conducted with chambers containing “dirty bedding” that consisted of the smell of several male and female rats. This was done to limit the (potential) effects of bedding odors after the switch.

Is mindfulness research methodology improving over time? No.

Is mindfulness research methodology improving over time? A systematic review. Simon B. Goldberg et al. PLOS One,


Background: Despite an exponential growth in research on mindfulness-based interventions, the body of scientific evidence supporting these treatments has been criticized for being of poor methodological quality.

Objectives: The current systematic review examined the extent to which mindfulness research demonstrated increased rigor over the past 16 years regarding six methodological features that have been highlighted as areas for improvement. These feature included using active control conditions, larger sample sizes, longer follow-up assessment, treatment fidelity assessment, and reporting of instructor training and intent-to-treat (ITT) analyses.

Data sources: We searched PubMed, PsychInfo, Scopus, and Web of Science in addition to a publically available repository of mindfulness studies.

Study eligibility criteria: Randomized clinical trials of mindfulness-based interventions for samples with a clinical disorder or elevated symptoms of a clinical disorder listed on the American Psychological Association’s list of disorders with recognized evidence-based treatment.

Study appraisal and synthesis methods: Independent raters screened 9,067 titles and abstracts, with 303 full text reviews. Of these, 171 were included, representing 142 non-overlapping samples.

Results: Across the 142 studies published between 2000 and 2016, there was no evidence for increases in any study quality indicator, although changes were generally in the direction of improved quality. When restricting the sample to those conducted in Europe and North America (continents with the longest history of scientific research in this area), an increase in reporting of ITT analyses was found. When excluding an early, high-quality study, improvements were seen in sample size, treatment fidelity assessment, and reporting of ITT analyses.

Conclusions and implications of key findings: Taken together, the findings suggest modest adoption of the recommendations for methodological improvement voiced repeatedly in the literature. Possible explanations for this and implications for interpreting this body of research and conducting future studies are discussed.

Virtually all irrationally inflated their moral qualities, & the absolute & relative magnitude was greater than in the other domains of positive self-evaluation

The Illusion of Moral Superiority. Ben M. Tappin, Ryan T. McKay. Social Psychological and Personality Science,

Abstract: Most people strongly believe they are just, virtuous, and moral; yet regard the average person as distinctly less so. This invites accusations of irrationality in moral judgment and perception—but direct evidence of irrationality is absent. Here, we quantify this irrationality and compare it against the irrationality in other domains of positive self-evaluation. Participants (N = 270) judged themselves and the average person on traits reflecting the core dimensions of social perception: morality, agency, and sociability. Adapting new methods, we reveal that virtually all individuals irrationally inflated their moral qualities, and the absolute and relative magnitude of this irrationality was greater than that in the other domains of positive self-evaluation. Inconsistent with prevailing theories of overly positive self-belief, irrational moral superiority was not associated with self-esteem. Taken together, these findings suggest that moral superiority is a uniquely strong and prevalent form of “positive illusion,” but the underlying function remains unknown.

Keywords: moral superiority, positive illusion, rationality, self-enhancement, social perception