Developmental Science最新文献

When adult men are made to feel gender-atypical, they often lash out with aggression, particularly when they are pressured (vs. autonomously motivated) to be gender-typical. Here, we examined the development of this phenomenon. Specifically, we provided a first experimental test of whether threatening adolescent boys' perceived gender typicality elicits aggression as a function of their pressured (vs. autonomous) motivation to be gender-typical. We also investigated whether this causal link emerges as a function of boys' chronological age versus pubertal development. Participants were a geographically diverse sample of 207 adolescent US boys (ages 10-14; 23.2% boys of color) and one of their parents. Boys played a "game" and received randomly-assigned feedback that their score was atypical versus typical of their gender. For boys in mid-to-late puberty (but not before), feedback that they are gender-atypical predicted an aggressive reaction, particularly among boys whose motivation to be gender-typical was pressured (vs. autonomous). Next, we explored which aspects of boys' social environments predicted their pressured motivation to be gender-typical. Boys' pressured motivation was positively correlated with their perceptions that their parents and peers would be "upset" if they deviated from gender norms, as well as with their parents' endorsement of so-called hegemonic beliefs about masculinity (i.e., that men should hold power over women). Parents with these beliefs resided in more conservative areas, had less formal education, and had lower incomes. Our results inform theorizing on gender identity development and lay the foundation for mitigating the harmful effects of gender typicality threat among adult men. RESEARCH HIGHLIGHTS: Similar to young adult men, adolescent boys in mid-to-late puberty (but not before) responded with aggression to perceived threats to their gender typicality. Aggression was heightened among boys whose motivation to be gender-typical was pressured (i.e., driven by social expectations) rather than autonomous. Which boys showed pressured motivation? Those whose parents endorsed hegemonic beliefs about masculinity (e.g., that men should have more power than people of other genders). Hegemonic beliefs about masculinity were strongest among parents who resided in more conservative US counties, had less formal education, and had lower incomes.

When exposed to rhythmic patterns with temporal regularity, adults exhibit an inherent ability to extract and anticipate an underlying sequence of regularly spaced beats, which is internally constructed, as beats are experienced even when no events occur at beat positions (e.g., in the case of rests). Perception of rhythm and synchronization to periodicity is indispensable for development of cognitive functions, social interaction, and adaptive behavior. We evaluated neural oscillatory activity in premature newborns (n = 19, mean age, 32 ± 2.59 weeks gestational age) during exposure to an auditory rhythmic sequence, aiming to identify early traces of periodicity encoding and rhythm processing through entrainment of neural oscillations at this stage of neurodevelopment. The rhythmic sequence elicited a systematic modulation of alpha power, synchronized to expected beat locations coinciding with both tones and rests, and independent of whether the beat was preceded by tone or rest. In addition, the periodic alpha-band fluctuations reached maximal power slightly before the corresponding beat onset times. Together, our results show neural encoding of periodicity in the premature brain involving neural oscillations in the alpha range that are much faster than the beat tempo, through alignment of alpha power to the beat tempo, consistent with observations in adults on predictive processing of temporal regularities in auditory rhythms. RESEARCH HIGHLIGHTS: In response to the presented rhythmic pattern, systematic modulations of alpha power showed that the premature brain extracted the temporal regularity of the underlying beat. In contrast to evoked potentials, which are greatly reduced when there is no sounds event, the modulation of alpha power occurred for beats coinciding with both tones and rests in a predictive way. The findings provide the first evidence for the neural coding of periodicity in auditory rhythm perception before the age of term.

Languages vary in their complexity; caregivers vary in the way they structure their communicative interactions with children; and boys and girls can differ in their language skills. Using a multilevel modelling approach, we explored how these factors influence the path of language acquisition for young children growing up around the world (mean age 2-years 9-months; 56 girls). Across 43 different sites, we analysed 103 mother-child pairs who spoke 3,170,633 utterances, 16,209,659 morphemes, divided across 20 different languages: Afrikaans, Catalan, Cantonese, Danish, Dutch, English, Farsi, French, German, Hebrew, Icelandic, Irish, Italian, Japanese, Mandarin, Norwegian, Portuguese, Spanish, Swedish and Turkish. Using mean length of utterance (MLU) as a measure of language complexity and developmental skill, we found that variation in children's MLU was significantly explained by (a) between-language differences; namely the rate of child MLU growth was attuned to the complexity of their mother tongue, and (b) between-mother differences; namely mothers who used higher MLUs tended to have children with higher MLUs, regardless of which language they were learning and especially in the very young (<2.5 years-old). Controlling for family and language environment, we found no evidence of MLU sex differences in child speech nor in the speech addressed to boys and girls. By modelling language as a multilevel structure with cross-cultural variation, we were able to disentangle those factors that make children's pathway to language different and those that make it alike. RESEARCH HIGHLIGHTS: The speech of 103 mother-child pairs from 20 different languages showed large variation in the path of early language development. Language, family, but not the sex of the child, accounted for a significant proportion of individual differences in child speech, especially in the very young. The rate at which children learned language was attuned to the complexity of their mother tongue, with steeper trajectories for more complex language. Results demonstrate the relative influence of culture, family, and sex in shaping the path of language acquisition for different children.

Following eye gaze is fundamental for many social-cognitive abilities, for example, when judging what another agent can or cannot know. While the emergence of gaze following has been thoroughly studied on a group level, we know little about (a) the developmental trajectory beyond infancy and (b) the sources of individual differences. In Study 1, we examined gaze following across the lifespan (N = 478 3- to 19-year-olds from Leipzig, Germany; and N = 240 20- to 80-year-old international, remotely tested adults). We found a steep performance improvement during preschool years, in which children became more precise in locating the attentional focus of an agent. Precision levels then stayed comparably stable throughout adulthood with a minor decline toward old age. In Study 2, we formalized the process of gaze following in a computational cognitive model that allowed us to conceptualize individual differences in a psychologically meaningful way (N = 60 3- to 5-year-olds, 50 adults). According to our model, participants estimate pupil angles with varying levels of precision based on observing the pupil location within the agent's eyes. In Study 3, we empirically tested how gaze following relates to vector following in non-social settings and perspective-taking abilities (N = 102 4- to 5-year-olds). We found that gaze following is associated with both of these abilities but less so with other Theory of Mind tasks. This work illustrates how the combination of reliable measurement instruments and formal theoretical models allows us to explore the in(ter)dependence of core social-cognitive processes in greater detail. RESEARCH HIGHLIGHTS: Gaze following develops beyond infancy. The highest precision levels in localizing attentional foci are reached in young adulthood with a slight decrease towards old age. We present a computational model that describes gaze following as a process of estimating pupil angles and the corresponding gaze vectors. The model explains individual differences and recovers signature patterns in the data. To estimate the relation between gaze- and vector following, we designed a non-social vector following task. We found substantial correlations between gaze following and vector following, as well as Level 2 perspective-taking. Other Theory of Mind tasks did not correlate.

Exposure to talker variability shapes how learning unfolds in the lab, and occurs in the everyday speech infants hear in daily life. Here, we asked whether aspects of talker variability in speech input are also linked to the onset of word production. We further asked whether these effects were redundant with effects of speech register (i.e., whether speech input was adult- vs. child-directed). To do so, we first extracted a set of highly common nouns from a longitudinal corpus of home recordings from North-American English-learning infants. We then used the acoustic variability in how these tokens were said to predict when the children first produced these same nouns. We found that in addition to frequency, variability in how words sound in 6-17 month's input predicted when children first said these words. Furthermore, while the proportion of child-directed speech also predicted the month of first production, it did so alongside measurements of acoustic variability in children's real-world input. Together, these results add to a growing body of literature suggesting that variability in how words sound in the input is linked to learning both in the lab and in daily life. RESEARCH HIGHLIGHTS: Talker variability shapes learning in the lab and exists in everyday speech; we asked whether it predicts word learning in the real world. Acoustic measurements of early words in infants' input (and their frequency) predicted when infants first said those same words. Speech register also predicted when infants said words, alongside effects of talker variability. Our results provide a deeper understanding of how sources of variability inherent to children's input connect to their learning and development.

There is substantial evidence that children's apparent omission of grammatical morphemes in utterances such as "She play tennis" and "Mummy eating" is in fact errors of commission in which contextually licensed unmarked forms encountered in the input are reproduced in a context-blind fashion. So how do children stop making such errors? In this study, we test the assumption that children's ability to recover from error is related to their developing sensitivity to longer-range dependencies. We use a pre-registered corpus analysis to explore the predictive value of different cues with regards to children's verb-marking errors and observe a developmental pattern consistent with this account. We look at context-independent cues (the identity of the specific verb being used) and at the relative value of context-dependent cues (the identity of the specific subject+verb sequence being used). We find that the only consistent effect across a group of 2- to 3-year-olds and a group of 3- to 4-year-olds is the relative frequency of unmarked forms of specific subject+verb sequences being used. The relative frequency of unmarked forms of the verb alone is predictive only in the younger age group. This is consistent with an account in which children recover from making errors by becoming progressively more sensitive to context, at first the immediately preceding lexical contexts (e.g., the subject that precedes the verb) and eventually more distant grammatical markers (e.g., the fronted auxiliary that precedes the subject in questions). RESEARCH HIGHLIGHTS: We provide a corpus analysis investigating input effects on young children's verb-marking errors (e.g., Mummy go) across development (between 2 and 4 years of age). We find evidence that these apparent errors of omission are in fact input-driven errors of commission that persist into the third year of life. We compare the relative effect on error rates of context-independent (e.g., verb) and context-dependent (e.g., subject+verb sequence) cues across developmental time. Our findings support the proposal that children recover from making verb-marking errors by becoming progressively more sensitive to preceding context.

In this study, we aimed to determine the role of parental praise and child affect in the neural processes underlying parent-child interactions, utilizing functional near-infrared spectroscopy (fNIRS) hyperscanning. We characterized the dynamic changes in interpersonal neural synchrony (INS) between parents and children (4-6 years old, n = 40 dyads) during a cognitively challenging task. We then examined how changes in parent-child INS are influenced by parental feedback and child affect. Parent-child INS showed a quadratic change over time, indicating a decelerated decline during the interaction period. The relationship of parental praise, in the form of positive feedback, to change in INS was contingent upon the child's positive affect during the task. The highest levels of INS were observed when praise was present and child affect was positive. The left temporo-parietal regions of the child and the right dorsolateral prefrontal and right temporo-parietal regions of the parent demonstrated the strongest INS. The dynamic change in INS during the interaction was associated with children's independent performance on a standardized test of visuospatial processing. This research, leveraging fNIRS hyperscanning, elucidates the neural dynamics underlying the interaction between parent praise and child positive affect, thereby contributing to our broader understanding of parent-child dynamics. RESEARCH HIGHLIGHTS: The level of interpersonal neural synchrony between parents and children dynamically varies during a cognitively challenging (tangram) task. The left temporo-parietal regions of the child and the right dorsolateral prefrontal and right temporo-parietal regions of the parent demonstrate the strongest parent-child neural synchrony. The relationship between parental praise (positive feedback) and parent-child neural synchrony is contingent upon child positive affect during the task. Change in parent-child neural synchrony relates to children's performance on an independent visuospatial processing measure.

Impaired numerosity perception in developmental dyscalculia (low "number acuity") has been interpreted as evidence of reduced representational precision in the neurocognitive system supporting non-symbolic number sense. However, recent studies suggest that poor numerosity judgments might stem from stronger interference from non-numerical visual information, in line with alternative accounts that highlight impairments in executive functions and visuospatial abilities in the etiology of dyscalculia. To resolve this debate, we used a psychophysical method designed to disentangle the contribution of numerical and non-numerical features to explicit numerosity judgments in a dot comparison task and we assessed the relative saliency of numerosity in a spontaneous categorization task. Children with dyscalculia were compared to control children with average mathematical skills matched for age, IQ, and visuospatial memory. In the comparison task, the lower accuracy of dyscalculics compared to controls was linked to weaker encoding of numerosity, but not to the strength of non-numerical biases. Similarly, in the spontaneous categorization task, children with dyscalculia showed a weaker number-based categorization compared to the control group, with no evidence of a stronger influence of non-numerical information on category choice. Simulations with a neurocomputational model of numerosity perception showed that the reduction of representational resources affected the progressive refinement of number acuity, with little effect on non-numerical bias in numerosity judgments. Together, these results suggest that impaired numerosity perception in dyscalculia cannot be explained by increased interference from non-numerical visual cues, thereby supporting the hypothesis of a core number sense deficit. RESEARCH HIGHLIGHTS: A strongly debated issue is whether impaired numerosity perception in dyscalculia stems from a deficit in number sense or from poor executive and visuospatial functions. Dyscalculic children show reduced precision in visual numerosity judgments and weaker number-based spontaneous categorization, but no increasing reliance on continuous visual properties. Simulations with deep neural networks demonstrate that reduced neural/computational resources affect the developmental trajectory of number acuity and account for impaired numerosity judgments. Our findings show that weaker number acuity in developmental dyscalculia is not necessarily related to increased interference from non-numerical visual cues.

How does the representation of boy and girl exemplars in curricular materials affect students' learning? We tested two competing hypotheses about the impact of gender exemplar on learning: First, in line with Social Learning Theory, children might exhibit a same-gender bias such that they prefer to learn from exemplars that match their gender (H1). Second, consistent with research on children's stereotypes about gender and math (e.g., associating boys with math competence), children might prefer to learn from exemplars who match their stereotypes about who is good at math (H2). We tested these hypotheses with children in middle school (N = 166), a time of development in which stereotypes are well-engrained, but before gender differences in math achievement appear. Children viewed two distinct math strategies, each presented by a boy or girl exemplar. We then examined which strategy children employed on a subsequent math test as well as their perceived similarity to the exemplars and their awareness or endorsement of gender-math stereotypes. Children did not preferentially learn from same-gender exemplars. However, children with stereotypes associating boys with math were more likely to learn the more difficult strategy when it was presented by a boy exemplar than children who did not associate boys with math. The results of this study provide valuable insight into how children's stereotypes impact their real-world learning. RESEARCH HIGHLIGHTS: How does the representation of boy and girl exemplars in children's curricular materials affect their learning? Past research demonstrates that children prefer to learn from same-gender exemplars, but also hold a stereotype that boys are better at math. In the current study, we test whether children preferentially adopt a math strategy presented by a boy or girl exemplar. Children who held the belief that boys are better at math were more likely to learn a difficult strategy from boy exemplars than children who did not endorse this stereotype.