The human capacity for rational decisions hinges on modal judgment: the discernment of what could, has to, or cannot happen. This ability was proposed to be a late outcome of human cognitive development, contingent on the mastery of linguistic structures. Here, we show that preschool-age children are capable of sophisticated forms of modal…

Mapping skills between different codes to represent numerical information, such as number symbols (i.e., verbal number words and written digits) and non-symbolic quantities, are important in the development of the concept of number. The aim of the current study is to investigate children's mapping skills by incorporating another numerical code…

Working memory (WM) is a critical cognitive system that supports processing a variety of information. Remembering different types of objects may impose different levels of cognitive demands on WM performance. In the present study, we examined 205 children's WM in representing different types of content and its developmental trajectories in early…

Severe psychosocial deprivation in early childhood experienced by institutionally reared children changes the course of structural brain development. Evidence from the Bucharest Early Intervention Project (BEIP) has demonstrated a causal association of random assignment to high-quality foster care intervention in early childhood with remediation…

Children often say that possible events are impossible, and only gradually come to see these events as possible. For instance, they often deny that people could do unusual things, like own a pet peacock, or immoral things, like stealing or lying. These possibility denials are surprising. For instance, children have first-hand experience with the…

As adults, we represent and think about number, space, and time in at least two ways: our intuitive--but imprecise--perceptual representations, and the slowly learned--but precise--number words. With development, these representational formats interface, allowing us to use precise number words to estimate imprecise perceptual experiences. We test…

We introduce a novel method to test a classic idea in developmental science that children's attention to a stimulus is driven by how much they can learn from it. Preschoolers (4-6 years, M=4.6) watched a video where a distracting animation accompanied static, page-by-page illustrations of a storybook. The audio narration for each storybook page…

This study examined whether grandparental support is a protective factor for children's socio-emotional development in the context of adversity. Using longitudinal data from the Millennium Cohort Study, we investigated the effects of grandparental support across development in children with and without adverse childhood experiences (ACEs).…

Executive control (EC) emerges in the first year of life, with the ability to inhibit prepotent responses (inhibitory control [IC]) and to flexibly readapt (cognitive flexibility [CF]) steadily improving. Simultaneously, electrophysiological brain activity undergoes profound reconfiguration, which has been linked to individual variability in EC.…

Before they even talk, infants become sensitive to the speech sounds of their native language and recognize the auditory form of an increasing number of words. Traditionally, these early perceptual changes are attributed to an emerging knowledge of linguistic categories such as phonemes or words. However, there is growing skepticism surrounding…

There are long-held concerns regarding the impact of screen media on children's cognitive development. In particular, fast pace and fantastical events have been theorized to deplete children's cognitive resources, leading to reductions in their attention and executive functions (EF). To date, however, empirical tests of short-term effects of media…

Does knowledge of other people's minds grow from concrete experience to abstract concepts? Cognitive scientists have hypothesized that infants' first-person experience, acting on their own goals, leads them to understand others' actions and goals. Indeed, classic developmental research suggests that before infants reach for objects, they do not…

Although exploratory play is considered a hallmark of cognitive development and learning, relatively few studies have been able to quantitatively characterize the shifts that may occur in children's approach to exploration. One reason for this gap is due to challenges coding and analyzing children's exploratory play behavior. In our paper, we…

A long-standing question in developmental science is how the neurodevelopment of the brain influences cognitive functions. Here, we examined the developmental change of resting EEG power and its links to vocabulary acquisition in school-age children. We further explored what mechanisms may mediate the relation between brain rhythm maturation and…

During human childhood, brain development and body growth compete for limited metabolic resources, resulting in a trade-off where energy allocated to brain development can decrease as body growth accelerates. This preregistered study explores the relationship between language skills, serving as a proxy for brain development, and body mass index at…