Beyond the average: walking infants take steps longer than their leg length

Traditionally, infant walking is characterized by small steps, attributed to limited balance control and strength. However, analyses of individual steps revealed that infants occasionally take large steps exceeding their leg length. These large steps provide evidence of advanced balance control and strength.     

Fourteen-month-old infants copy an action style accompanied by social-emotional cues

Human adults exaggerate their actions and facial expressions when interacting with infants. These infant-directed modifications highlight certain aspects of action sequences and attract infants’ attention. This study investigated whether social-emotional aspects of infant-directed modifications, such as smiling, eye contact, and onomatopoeic vocalization, influence infants’ copying of another's action, especially action style, during the process of achieving an outcome. In Study 1, 14-month-old infants (n = 22) saw an experimenter demonstrate goal-directed actions in an exaggerated manner. Either the style or the end state of the actions was accompanied by social-emotional cues from the experimenter. Infants copied the style of the action more often when social-emotional cues accompanied the style than when they accompanied the end state. In Study 2, a different group of 14-month-old infants (n = 22) watched the same exaggerated actions as in Study 1, except that either the style or the end state was accompanied by a physical sound instead of social-emotional cues. The infants copied the end state consistently more often than the style. Taken together, these two studies showed that accompanying social-emotional cues provided by a demonstrator, but not accompanying physical sound, increased infants’ copying of action style. These findings suggest that social-emotional cues facilitate efficient social learning through the adult–infant interaction.     

Male life-course persistent antisocial behavior: A review of neurodevelopmental factors

Life-course-persistent antisocial behavior, which is almost exclusively male, is arguably the single most important child clinical problem. The neurodevelopmental factors which contribute to this markedly male predominance stem from the greater male vulnerability to inherited and acquired neurodevelopmental impairments which increase the risk for antisocial behavior. The factors that contribute to this greater male vulnerability are discussed, and implications for prevention are presented.     

Fruit over sunbed: Carotenoid skin colouration is found more attractive than melanin colouration

Skin colouration appears to play a pivotal part in facial attractiveness. Skin yellowness contributes to an attractive appearance and is influenced both by dietary carotenoids and by melanin. While both increased carotenoid colouration and increased melanin colouration enhance apparent health in Caucasian faces by increasing skin yellowness, it remains unclear, firstly, whether both pigments contribute to attractiveness judgements, secondly, whether one pigment is clearly preferred over the other, and thirdly, whether these effects depend on the sex of the face. Here, in three studies, we examine these questions using controlled facial stimuli transformed to be either high or low in (a) carotenoid colouration, or (b) melanin colouration. We show, firstly, that both increased carotenoid colouration and increased melanin colouration are found attractive compared to lower levels of these pigments. Secondly, we show that carotenoid colouration is consistently preferred over melanin colouration when levels of colouration are matched. In addition, we find an effect of the sex of stimuli with stronger preferences for carotenoids over melanin in female compared to male faces, irrespective of the sex of the observer. These results are interpreted as reflecting preferences for sex-typical skin colouration: men have darker skin than women and high melanization in male faces may further enhance this masculine trait, thus carotenoid colouration is not less desirable, but melanin colouration is relatively more desirable in males compared to females. Taken together, our findings provide further support for a carotenoid-linked health-signalling system that is highly important in mate choice.     

Exploring temperamental differences in infants from the USA and the Netherlands

This longitudinal study employed the Infant Behaviour Questionnaire-Revised in assessing temperamental differences between infants at 6 months (n = 114 US, 184 Dutch) and 12 months (n = 92 US, 172 Dutch) from the USA and the Netherlands. Main effects indicated that Dutch infants were rated higher on the Orienting/Regulatory Capacity (ORC) factor and fine-grained dimensions of smiling and laughter, falling reactivity, cuddliness, low-intensity pleasure, and soothability, whereas US infants received higher ratings on the Negative Affectivity factor and on dimensions of activity level, vocal reactivity, fear, frustration, and sadness. Cultural differences for ORC were more pronounced in early infancy, cultural differences for Fear were stronger in late infancy, and US infants demonstrated higher duration of orienting at 12 months only. Culture also appeared to impact the pace of consolidation of temperamental characteristics, with greater stability exhibited by US than Dutch infants in smiling and laughter and vocal reactivity.     

An investigation of mental rotation in infancy using change detection

Two experiments were conducted to examine mental rotation in 6- to 12-month-old infants (N = 166) using a change detection task. These experiments were replications of Lauer and Lourenco (Lauer et al., 2015; Lauer & Lourenco, 2016), using identical stimuli and variations of their procedure, including an exact replication conducted in a laboratory setting (Experiment 1), and an online assessment using Lookit (Scott et al.,2017; Scott & Schulz, 2017) (Experiment 2). Both experiments failed to replicate the results of the original study; in neither experiment did infants’ behavior provide evidence that they mentally rotated the object. Results are discussed in terms of the robustness of mental rotation in infancy and about limits in our experimental procedures for uncovering perceptual and cognitive abilities in infants.     

Male risk-taking as a context-sensitive signaling device

Evolutionary theorists have suggested that sex differences in risk-taking are due ultimately to greater intrasexual competition among men (compared with women) over access to mating opportunities. The current work provides one of the first direct tests of the hypothesis that risk-taking serves self-presentational functions associated with mating. Results of an experimental study indicated a strong positive relationship between sexual arousal and risk-taking, but only in men exposed to a romantically available female confederate who purportedly would view their risk-taking performance. Findings suggest that risk-taking can serve as a signaling device in the context of mating, that this function is sex-specific, and that it is highly sensitive both to the situational context and to the current psychological state of the risk-taker. This research highlights the utility of an evolutionary approach in understanding the proximate social psychological determinants of risky decision-making.     

Relational categories are more mutable than entity categories

Across three experiments, we explore differences between relational categories—whose members share common relational patterns—and entity categories, whose members share common intrinsic properties. Specifically, we test the claim that relational concepts are more semantically mutable in context, and therefore less stable in memory, than entity concepts. We compared memory for entity nouns and relational nouns, tested either in the same context as at encoding or in a different context. We found that (a) participants show better recognition accuracy for entity nouns than for relational nouns, and (b) recognition of relational nouns is more impaired by a change in context than is recognition of entity nouns. We replicated these findings even when controlling for factors highly correlated with relationality, such as abstractness–concreteness. This suggests that the contextual mutability of relational concepts is due to the core semantic property of conveying relational structure and not simply to accompanying characteristics such as abstractness. We note parallels with the distinction between nouns and verbs and suggest implications for lexical and conceptual structure. Finally, we relate these patterns to proposals that a deep distinction exists between words with an essentially referential function and those with a predicate function.     

Size does matter: Women mentally rotate large objects faster than men

Performance in a computerized “mental rotation” task was measured in groups of males and females while they rotated Shepard‐Metzler‐like cube assemblies on either a standard laptop screen (size = 36 cm) or on a large display wall (584 cm) where the stimuli appeared at considerably larger sizes and within a much wider field of view than that typically used in most spatial tasks. Males and females did not differ significantly in performance in the standard size condition with regards to response time but females performed faster than males in the large display condition. Males were also found to be significantly more accurate than females, regardless of display. We found no sign of trading accuracy for speed for either of the sexes or screen size conditions. We surmise that such an effect may be due to differences in task‐solving strategies between the sexes, where a holistic strategy – which may be preferred by males is negatively affected by large object sizes, whereas a piecemeal approach, that may be preferred by females, is virtually unaffected by display size.     

Men dissociate sexual attraction from moral judgement more than women

Would you find an opposite‐sex individual physically less attractive if you knew that he/she was a bad person? Would you feel the same if you were a man or a woman? This study examined whether gender differences exist in the influence of moral judgements on heterosexual physical attraction. In a first Experiment, participants (N = 214) rated on attractiveness photographs of opposite‐sex persons. Each photograph was paired with a “good” and a “bad” (from a moral point of view) sentence to depict a quality or activity of the displayed person (i.e., she/he is a defender of human rights in an NGO vs. she/he belongs to a terrorist group). Compared with women, men were significantly less influenced by sentence valence in their attractiveness ratings. A second Experiment (N = 105) using photographs of very attractive people showed the same pattern of results. The data suggest that sexual attraction is relatively less permeable to moral factors in men, and that this sex difference is consistent with an evolutionary approach to human sexuality.     

Gender, jealousy, and attachment: A (more) thorough examination across measures and samples

We examined the role of attachment and gender on responses to hypothetical sexual and emotional infidelity. Unlike previous studies, both categorical and continuous attachment style and infidelity distress measures were administered to separate samples of college students and adults. Consistent with previous jealousy research, we found moderate gender differences on forced-choice measures of infidelity distress but smaller differences on continuous measures. However, across all analyses, attachment style was not a significant predictor. We discuss this failure to replicate Levy and Kelly (2010) and provide suggestions for future research.     

Age differences in moral judgment: Older adults are more deontological than younger adults

In 2 studies, an older and a younger age group morally evaluated dilemmas contrasting a deontological judgment (do not harm others) against a utilitarian judgment (do what is best for the majority). Previous research suggests that deontological moral judgments are often underpinned by affective reactions and utilitarian moral judgments by deliberative thinking. Separately, research on the psychology of aging has shown that affect plays a more prominent role in the judgments and decision making of older (vs. younger) adults. Yet age remains a largely overlooked factor in moral judgment research. Here, we therefore investigated whether older adults would make more deontological judgments on the basis of experiencing different affective reactions to moral dilemmas as compared with younger adults. Results from 2 experiments indicated that older adults made significantly more deontological moral judgments. Mediation analyses revealed that the relationship between age and making more deontological moral judgments is partly explained by older adults exhibiting significantly more negative affective reactions and having more morally idealistic beliefs as compared with younger adults.     

Individual differences in category learning: sometimes less working memory capacity is better than more

We examined whether individual differences in working memory influence the facility with which individuals learn new categories. Participants learned two different types of category structures: rule-based and information-integration. Successful learning of the former category structure is thought to be based on explicit hypothesis testing that relies heavily on working memory. Successful learning of the latter category structure is believed to be driven by procedural learning processes that operate largely outside of conscious control. Consistent with a widespread literature touting the positive benefits of working memory and attentional control, the higher one’s working memory, the fewer trials one took to learn rule-based categories. The opposite occurred for information-integration categories - the lower one’s working memory, the fewer trials one took to learn this category structure. Thus, the positive relation commonly seen between individual differences in working memory and performance can not only be absent, but reversed. As such, a comprehensive understanding of skill learning - and category learning in particular - requires considering the demands of the tasks being performed and the cognitive abilities of the performer.     

Body movements of male and female speakers and their influence on perceptions of personality

Men and women score differently on some personality traits and people’s behavior reflects who they are. Therefore, males and females could be expected to express themselves differently on a behavioral level. To test this idea we turned the public performances of speakers (20 female and 20 male) into stick figure movies. Students of the University of Vienna (n = 150) rated these movies on scales measuring the Big Five personality traits. The participants experienced difficulties in ascribing the correct sex to the stick figures. Nevertheless, stick figures representing male speakers received higher ratings for extraversion and emotional stability than stick figure animations of female speakers. In addition, gender stereotypes seemed to influence the participants’ ratings. Agreeableness, for instance, was preferably classified as female trait. In conclusion, our results suggest that body motion conveys social information, that men and women present themselves differently, and that people’s judgments are influenced by gender stereotypes.     

When the poor give more than the rich: The role of resource evaluability on relative giving

Five experiments examined the role of resource evaluability on giving. We systematically varied participants' resources they and another potential donor received and whether they could donate to a recipient either by themselves or with the other donor. Participants in the relative advantage condition received more resources than the other donor, and those in the relative disadvantage condition received fewer resources than the other donor. The presence of the other donor made participants' resources evaluable and shaped giving: Relatively disadvantaged participants were proportionally more generous than advantaged participants but only when they could evaluate their resources. Neither the mere presence of others nor reputational concerns could explain the results. Exploratory mediation and moderation analyses further showed that relatively disadvantaged participants give proportionally more the higher and the more equal they perceive their status to the advantaged donor. This shows that the generosity of those who have less does depend on how they evaluate their status compared to other donors. Our results provide insights into the question of why and when resource asymmetries between donors result in prosocial giving and can influence fundraising strategies of charitable organizations.     

Angry faces are more resistant to forgetting than are happy faces: directed forgetting effects on the identity of emotional faces

Using the item-method directed forgetting paradigm (i.e. intentionally forgetting specified information), we examined directed forgetting of facial identity as a function of facial expression and the sex of the expresser and perceiver. Participants were presented with happy and angry male and female faces cued for either forgetting or remembering, and were then asked to recognise previously studied faces from among a series of neutral faces. For each recognised test face, participants also recalled the face’s previously displayed emotional expression. We found that angry faces were more resistant to forgetting than were happy faces. Furthermore, angry expressions on male faces and happy expressions on female faces were recognised and recalled better than vice versa. Signal detection analyses revealed that male faces gave rise to a greater sensitivity than female faces did, and male participants, but not female participants, showed greater sensitivity to male faces than to female faces. Several theoretical implications are discussed.