Metacognitive reasoning is central to decision-making. For every decision, we can also judge our trust in that decision, or our level of "confidence." The mechanisms and representations underlying reasoning about confidence remain debated. We test whether children rely on "processing fluency" to infer their own confidence: do…

Children learn language by listening to speech from caregivers around them. However, the type and quantity of speech input that children are exposed to change throughout early childhood in ways that are poorly understood due to the small samples (few participants, limited hours of observation) typically available in developmental psychology. Here…

Preverbal infants spontaneously represent the number of objects in collections. Is this 'sense of number' (also referred to as Approximate Number System, ANS) part of the cognitive foundations of mathematical skills? Multiple studies reported a correlation between the ANS and mathematical achievement in children. However, some have suggested that…

Musical training has long been viewed as a model for experience-dependent brain plasticity. Reports of musical training-induced brain plasticity are largely based on cross-sectional studies comparing musicians to non-musicians, which cannot address whether musical training itself is sufficient to induce these neurobiological changes or whether…

For many years, researchers studied executive functions (EFs) in the laboratory with a focus on understanding an individual child's development and brain processes in a controlled environment. Building on this foundational research, there is a growing interest in EFs in the context of a child's dynamic, social world, and the contextual and…

How do children construct a concept of natural numbers? Past research addressing this question has mainly focused on understanding how children come to acquire the cardinality principle. However, at that point children already understand the first number words and have a rudimentary natural number concept in place. The question therefore remains;…

Mutualism is a developmental theory that posits positive reciprocal relationships between distinct cognitive abilities during development. It predicts that abilities such as language and reasoning will influence each other's rates of growth. This may explain why children with Language Disorders also tend to have lower than average non-verbal…

The majority of evidence on the interplay between academic and non-academic skills comes from high-income countries. The aim of this study was to examine the bidirectional associations between Ghanaian children's executive function, social-emotional, literacy, and numeracy skills longitudinally. Children (N = 3,862; M age = 5.2 years at time 1)…

Although growing evidence suggests a link between children's math skills and their ability to estimate numerical quantities using the approximate number system (ANS), little is known about the sources underlying individual differences in ANS acuity and their relation with specific mathematical skills. To examine the role of intergenerational…

Using existing longitudinal data from 570 infants in the Maternal Lifestyle Study, we explored the predictive value of maternal and infant affect and maternal vocalizations during 2 minutes of face-to-face interactions at 4 months on IQ scores at 4.5 and 7 years. After controlling for demographic factors, maternal depression, and prenatal drug…

Bilingual preschoolers often perform better than monolingual children on false-belief understanding. It has been hypothesized that this is due to their enhanced executive function skills, although this relationship has rarely been tested or supported. The current longitudinal study tested whether metalinguistic awareness was responsible for this…

Face recognition difficulties are frequently documented in children with autism spectrum disorders (ASD). It has been hypothesized that these difficulties result from a reduced interest in faces early in life, leading to decreased cortical specialization and atypical development of the neural circuitry for face processing. However, a recent study…

In this 8-year longitudinal study, we traced the vocabulary growth of Chinese children, explored potential precursors of vocabulary knowledge, and investigated how vocabulary growth predicted future reading skills. Two hundred and sixty-four (264) native Chinese children from Beijing were measured on a variety of reading and language tasks over…

The current longitudinal study examined the role of cumulative social risk on children's theory of mind (ToM) and executive functioning (EF) across early development. Further, we also tested a cascade model of development in which children's social cognition at 18 months was hypothesized to predict ToM and EF at age 4.5 through intermediary…

Young children engage in essentialist reasoning about natural kinds, believing that many traits are innately determined. This study investigated whether personal experience with second language acquisition could alter children's essentialist biases. In a switched-at-birth paradigm, 5- and 6-year-old monolingual and simultaneous bilingual…