Children with delays in expressive language (late talkers) have heterogeneous developmental trajectories. Some are late bloomers who eventually "catch-up," but others have persisting delays or are later diagnosed with developmental language disorder (DLD). Early in development it is unclear which children will belong to which group. We…

Questions about early word knowledge pervade the literature on both typical and atypical language trajectories. To determine which words an infant knows, researchers have relied on two types of measures--caregiver-report and eye-gaze behavior. When these measures are compared, however, their results frequently fail to converge, making it difficult…

Executive functions (EFs) emerge in the first years of life and are essential for many areas of child development. However, intraindividual developmental trajectories of EF during toddlerhood and their associations with ongoing development of language skills remain poorly understood. The present three-wave study examined these trajectories and…

Studies of hemispheric specialization have traditionally cast the left hemisphere as specialized for language and the right hemisphere for spatial function. Much of the supporting evidence for this separation of function comes from studies of healthy adults and those who have sustained lesions to the right or left hemisphere. However, we know…

While day-to-day negative affect normatively rises across adolescence, emotional experiences also stratify, or diverge, across individuals. Moreover, negative affect is not a unitary construct but comprises distinct feeling states (e.g., sadness, anger, anxiety), each characterized by distinct age-related trends. Yet, most developmental research…

Although identifying the referents of single words is often cited as a key challenge for getting word learning off the ground, it overlooks the fact that young learners consistently encounter words in the context of other words. How does this company help or hinder word learning? Prior investigations into early word learning from children's…

Socioeconomic status (SES) has been repeatedly linked to the developmental trajectory of vocabulary acquisition in young children. However, the nature of this relationship remains underspecified. In particular, despite an extensive literature documenting young children's reliance on a host of skills and strategies to learn new words, little…

Research has shown that infants are curious and actively seek situations from which they can learn. For instance, a recent eye-tracking study demonstrates that babies tend to allocate their attention to stimuli that offer opportunities for learning new information. Interestingly, however, the degree to which attention is guided by information gain…

Many previous studies indicate that children are highly sensitive to the immoral behavior of others, preferring prosocial over antisocial characters. Accordingly, children avoid transgressors from a very early age. A special kind of transgressor is the moral hypocrite, who not only acts immorally but also acts in contrast to what they preach.…

Doll play provides opportunities for children to practice social skills by creating imaginary worlds, taking others' perspectives, and talking about others' internal states. Previous research using functional near-infrared spectroscopy (fNIRS) found a region over the posterior superior temporal sulcus (pSTS) was more active during solo doll play…

Physiological synchrony is an important biological process during which parent-child interaction plays a significant role in shaping child socioemotional adjustment. The present study held a context-dependent perspective to examine the conditional association between parent-child physiological synchrony and child socioemotional adjustment (i.e.,…

The speech register that adults especially caregivers use when interacting with infants and toddlers, that is, infant-directed speech (IDS) or baby talk, has been reported to facilitate language development throughout the early years. However, the neural mechanisms as well as why IDS results in such a developmental faciliatory effect remain to be…

Mature social evaluations privilege agents' intentions over the outcomes of their actions, but young children often privilege outcomes over intentions in verbal tasks probing their social evaluations. In three experiments (N = 118), we probed the development of intention-based social evaluation and mental state reasoning using nonverbal methods…

This study investigates how neural networks address the properties of children's linguistic knowledge, with a focus on the "Agent-First" strategy in comprehension of an active transitive construction in Korean. We develop various neural-network models and measure their classification performance on the test stimuli used in a behavioural…

Parents with fewer educational and economic resources (low socioeconomic-status, SES) tend to speak less to their children, with consequences for children's later life outcomes. Despite this well-established and highly popularized link, less research addresses why the SES "word gap" exists. Moreover, while research has assessed…