Children and Adults Selectively Attribute Shared Cultural Knowledge to Speakers of the Same Language

Children's and adults’ attributions of shared knowledge of and shared preference for songs were investigated across two prominent social categories: language and gender. Both attributions indicate similarity among individuals but shared cultural knowledge can be more informative about common social history than shared preference, as it is mainly transferred through social interactions within cultures, while preferences can have various sources. Both 5- to 6-year-old children (N = 60) and adults (N = 160) generalized knowledge of songs across individuals who speak the same-language rather than same-gender individuals. In contrast, preference for songs was not systematically generalized across either category. Thus, individuals selectively infer shared cultural knowledge among same-language speakers, suggesting an early emerging link between shared knowledge and cultural boundaries.     

Judging a Book by Its Cover: Children's Facial Trustworthiness as Judged by Strangers Predicts Their Real-World Trustworthiness and Peer Relationships

This longitudinal research examined whether children's facial trustworthiness as judged by strangers can predict their real-world trustworthiness and peer acceptance. Adults (Study 1) and children (Study 2) judged the facial trustworthiness of 8- to 12-year-old children (N = 100) solely based on their photographs. The children's classmates were asked to report their real-world trustworthiness and peer acceptance. Children's facial trustworthiness reliably predicted these outcomes both initially when the photographs were taken, as well as 1 year later, and this effect was mediated by the initial ratings of real-world trustworthiness and peer acceptance. These results provide evidence for a long-lasting linkage between children's facial and real-world trustworthiness.     

A Long-Term Effect of Perceptual Individuation Training on Reducing Implicit Racial Bias in Preschool Children

This study tracked the long-term effect of perceptual individuation training on reducing 5-year-old Chinese children's (N = 95, M_age = 5.64 years) implicit pro-Asian/anti-Black racial bias. Initial training to individuate other-race Black faces, followed by supplementary training occurring 1 week later, resulted in a long-term reduction of pro-Asian/anti-Black bias (70 days). In contrast, training Chinese children to recognize White or Asian faces had no effect on pro-Asian/anti-Black bias. Theoretically, the finding that individuation training can have a long-term effect on reducing implicit racial bias in preschoolers suggests that a developmentally early causal linkage between perceptual and social processing of faces is not a transitory phenomenon. Practically, the data point to an effective intervention method for reducing implicit racism in young children.     

Carving Metacognition at Its Joints: Protracted Development of Component Processes

Two experiments investigated the development of metacognitive monitoring and control, and conditions under which children engage these processes. In Experiment 1, 5‐year‐olds (N = 30) and 7‐year‐olds (N = 30), unlike adults (N = 30), showed little evidence of either monitoring or control. In Experiment 2, 5‐year‐olds (N = 90) were given performance feedback (aimed at improving monitoring), instruction to follow a particular strategy (aimed at improving control), or both. Across conditions, feedback improved children's monitoring, and instruction improved both monitoring and control. Thus, children's poor metacognitive performance likely reflects a difficulty engaging the component processes spontaneously rather than a lack of metacognitive ability. These findings also suggest that the component processes are distinct, with both undergoing protracted development.     

How children revise their beliefs in light of reasons

We investigate how the ability to respond appropriately to reasons provided in discourse develops in young children. In Study 1 (N = 58, Germany, 26 girls), 4- and 5-, but not 3-year-old children, differentiated good from bad reasons. In Study 2 (N = 131, Germany, 64 girls), 4- and 5-year-old children considered both the strength of evidence for their initial belief and the quality of socially provided reasons for an alternative view when deciding whether to change their minds. Study 3 (N = 80, the United States, 42 girls, preregistered) shows that 4- and 5-year-old children also consider meta-reasons (reasons about reasons) in their belief revision. These results suggest that by age 4, children possess key critical thinking capacities for participating in public discourse.     

Superior Detection of Faces in Male Infants at 2 Months

Females generally attend more to social information than males; however, little is known about the early development of these sex differences. With eye tracking, 2-month olds’ (N = 101; 44 females) social orienting to faces was measured within four-item image arrays. Infants were more likely to detect human faces compared to objects, suggesting a functional face detection system. Unexpectedly, males looked longer at human faces than females, and only males looked faster and longer at human faces compared to objects. Females, in contrast, looked less at human faces relative to animal faces and objects, appearing socially disinterested. Notably, this is the first report of a male face detection advantage at any age. These findings suggest a unique stage in early infant social development.     

Teacher depressive symptoms and children's school readiness in Ghana

This study investigated associations between kindergarten teachers' (N = 208) depressive symptoms and students' (Ghanaian nationals, N = 1490, M_age = 5.8) school-readiness skills (early literacy, early numeracy, social–emotional skills, and executive function) across 208 schools in Ghana over one school year. Teachers' depressive symptoms in the fall negatively predicted students' overall school-readiness skills in the spring, controlling for school-readiness skills in the fall. These results were primarily driven by social–emotional skills (r = .1–.3). There was evidence of heterogeneity by students' fall skill levels; teacher depressive symptoms predicted more negative spring overall school readiness for children who had higher fall school-readiness skills. Findings underscore the importance of teachers' mental health in early childhood education globally, with implications for policy and practice.     

A robot is watching me!: Five-year-old children care about their reputation after interaction with a social robot

Since robots are becoming involved in children's lives, it is urgent to determine how children perceive robots. The present study assessed whether Japanese 5-year-olds care about their reputation when interacting with a social robot. Children were given stickers and asked to divide them between themselves and an absent recipient. Results revealed that children (N = 112, 55 boys, 57 girls) strategically shared more stickers when being watched by a social interactive robot than by an attentional but non-interactive robot or a still robot. Additionally, children (N = 36, 18 boys, 18 girls) attributed higher psychological properties to social robots. This study is the first to show that 5-year-olds care about their reputations from social robots.     

Rock With Me: The Role of Movement Synchrony in Infants' Social and Nonsocial Choices

Matching the timing of one's movements to the movements of others has been proposed to increase affiliation and prosociality. Although coordinated movements facilitate early social interactions, not much is known about the mechanisms and effects of movement synchrony throughout development. Two studies investigated 12‐month‐olds' (Study 1, N = 40) and 9‐month‐olds' (Study 2, N = 41) preferences for synchronous others in a social as opposed to a nonsocial context. It was found that movement synchrony exclusively guides infants' social choices at 12 months. In contrast, 9‐month‐olds did not show any preferences for synchronous movements in social or nonsocial contexts. Results suggest that movement synchrony is important in guiding infants' social preferences and its effects emerge toward the end of the 1st year of life.     

Children's Initial Responses and Beyond: Effects of Niceness and Similarity on Preference,Giving, and Memory

This study assessed children's preference, giving, and memory to investigate the impact of social information over time. We compared 5- and 6-year-olds’ (N = 144) immediate or delayed responses to an individual who does or does not share their toy preference (similar vs. dissimilar) or an individual who treats others kindly or poorly (nice vs. mean). Immediately, children all preferred the similar or nice characters but gave more stickers to the similar character. This strong initial effect of similarity was not evident after 1 week; children's preference, giving, and memory reflected a greater long-term impact of niceness than similarity. These findings highlight the importance of using multiple features and measures to elucidate children's evolving views about others.     

Relations Among Chronic Peer Group Rejection,Maladaptive Behavioral Dispositions,and Early Adolescents' Peer Perceptions

Adolescents' perceptions of peers' relational characteristics (e.g., support, trustworthiness) were examined for subtypes of youth who evidenced chronic maladaptive behavior, chronic peer group rejection, or combinations of these risk factors. Growth mixture modeling was used to identify subgroups of participants within a normative sample of youth (N = 477; 50% female) for whom data had been gathered from fifth grade (M_age = 10.61) through eighth grade (M_age = 13.93). Results revealed that both enduring individual vulnerability (i.e., chronic withdrawn or chronic aggressive behavioral dispositions) and interpersonal adversity (i.e., chronic peer group rejection) were linked with either differences or changes in adolescents' perceptions of their peers' supportiveness and trustworthiness across the early adolescent age period.     

The Development of Simile Comprehension: From Similarity to Scalar Implicature

Similes require two different pragmatic skills: appreciating the intended similarity and deriving a scalar implicature (e.g., “Lucy is like a parrot” normally implies that Lucy is not a parrot), but previous studies overlooked this second skill. In Experiment 1, preschoolers (N = 48; ages 3–5) understood “X is like a Y” as an expression of similarity. In Experiment 2 (N = 99; ages 3–6, 13) and Experiment 3 (N = 201; ages 3–5 and adults), participants received metaphors (“Lucy is a parrot”) or similes (“Lucy is like a parrot”) as clues to select one of three images (a parrot, a girl or a parrot-looking girl). An early developmental trend revealed that 3-year-olds started deriving the implicature “X is not a Y,” whereas 5-year-olds performed like adults.     

Gahvora cradling in Tajikistan: Cultural practices and associations with motor development

In Tajikistan, infants are bound supine in a “gahvora” cradle that severely restricts movement. Does cradling affect motor development and body growth? In three studies (2013–2018), we investigated associations between time in the gahvora (within days and across age) and motor skills and flattened head dimensions in 8–24-month-old Tajik infants (N = 269, 133 girls, 136 boys)) and 4.3–5.1-year-old children (N = 91, 53 girls, 38 boys). Infants had later motor onset ages relative to World Health Organization standards and pronounced brachycephaly; cradling predicted walk onset age and the proficiency of sitting, crawling, and walking. By 4–5 years, children's motor skills were comparable with US norms. Cultural differences in early experiences offer a unique lens onto developmental processes and equifinality in development.     

White children's empathy-related responding and prosocial behavior toward White and Black children

Relations among White (non-Latinx) children's empathy-related responding, prosocial behaviors, and racial attitudes toward White and Black peers were examined. In 2017, 190 (54% boys) White 5- to 9-year-old children (M = 7.09 years, SD = 0.94) watched a series of videos that depicted social rejection of either a White or Black child. Empathy-related responses, prosocial behaviors, and racial attitudes were measured using multiple methods. Results showed that younger children showed less facial concern toward Black than White peers and greater increases with age in concern and prosocial behaviors (sharing a desirable prize) for Black, compared to White, targets. Children's facial anger increased with age for White but not Black targets. The findings can extend our understanding children's anti-racism development.     

The Development of Selective Copying: Children's Learning From an Expert Versus Their Mother

This study tested the prediction that, with age, children should rely less on familiarity and more on expertise in their selective social learning. Experiment 1 (N = 50) found that 5‐ to 6‐year‐olds copied the technique their mother used to extract a prize from a novel puzzle box, in preference to both a stranger and an established expert. This bias occurred despite children acknowledging the expert model's superior capability. Experiment 2 (N = 50) demonstrated a shift in 7‐ to 8‐year‐olds toward copying the expert. Children aged 9–10 years did not copy according to a model bias. The findings of a follow‐up study (N = 30) confirmed that, instead, they prioritized their own—partially flawed—causal understanding of the puzzle box.     

The Development of Nonsymbolic Probability Judgments in Children

Two experiments were designed to investigate the developmental trajectory of children's probability approximation abilities. In Experiment 1, results revealed 6- and 7-year-old children's (N = 48) probability judgments improve with age and become more accurate as the distance between two ratios increases. Experiment 2 replicated these findings with 7- to 12-year-old children (N = 130) while also accounting for the effect of the size and the perceived numerosity of target objects. Older children's performance suggested the correct use of proportions for estimating probability; but in some cases, children relied on heuristic shortcuts. These results suggest that children's nonsymbolic probability judgments show a clear distance effect and that the acuity of probability estimations increases with age.     

Frontal asymmetry assessed in infancy using functional near-infrared spectroscopy is associated with emotional and behavioral problems in early childhood

Frontal asymmetry (FA), the difference in brain activity between the left versus right frontal areas, is thought to reflect approach versus avoidance motivation. This study (2012–2021) used functional near-infrared spectroscopy to investigate if infant (M_age = 7.63 months; N = 90; n = 48 male; n = 75 White) FA in the dorsolateral prefrontal cortex relates to psychopathology in later childhood (M_age = 62.05 months). Greater right FA to happy faces was associated with increased internalizing (η² = .09) and externalizing (η² = .06) problems at age 5 years. Greater right FA to both happy and fearful faces was associated with an increased likelihood of a lifetime anxiety diagnosis (R² > .13). FA may be an informative and early-emerging marker for psychopathology.     

Children's Norm Enforcement in Their Interactions With Peers

This study investigates how children negotiate social norms with peers. In Study 1, 48 pairs of 3‐ and 5‐year‐olds (N = 96) and in Study 2, 48 pairs of 5‐ and 7‐year‐olds (N = 96) were presented with sorting tasks with conflicting instructions (one child by color, the other by shape) or identical instructions. Three‐year‐olds differed from older children: They were less selective for the contexts in which they enforced norms, and they (as well as the older children to a lesser extent) used grammatical constructions objectifying the norms (“It works like this” rather than “You must do it like this”). These results suggested that children's understanding of social norms becomes more flexible during the preschool years.     

The development of uncertainty monitoring during kindergarten: Change and longitudinal relations with executive function and vocabulary in children from low-income backgrounds

Children's ability to monitor subjective feelings of uncertainty (i.e., engage in uncertainty monitoring) is a central metacognitive skill. In the current study, we examined the development of uncertainty monitoring as well as its relations with vocabulary and executive function development in children (N = 137, 52% female) from predominately White and Latinx/Hispanic backgrounds when they were 4–6 years old and enrolled in a Head Start preschool and kindergarten between 2018 and 2019. We found that children's uncertainty monitoring improved during the kindergarten year. Children's executive function and vocabulary in preschool and vocabulary growth from preschool to kindergarten predicted uncertainty monitoring at the end of kindergarten, which sheds new light on potential mechanisms supporting children's metacognitive development.