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…

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 with poor reading comprehension tend to have oral language weaknesses, suggesting that poor language in the early years is a proximal cause of later reading comprehension difficulties. Yet, longitudinal studies have not succeeded in reliably predicting which children go on to have comprehension weaknesses (CW), and evidence comprises…

Developmental psychology focuses on how psychological constructs change with age. In cognitive development research, however, the specifics of this emergence is often underspecified. Researchers often provisionally assume linear growth by including chronological age as a predictor in regression models. In this work, we aim to evaluate this…

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…

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.…

Parental socioeconomic status (SES) is a well-established predictor of children's neurocognitive development. Several theories propose that specific cognitive skills are particularly vulnerable. However, this can be challenging to test, because cognitive assessments are not pure measures of distinct neurocognitive processes, and scores across…

Across the early childhood period of development, young children exhibit considerable growth in their executive functioning (EF) and vocabulary abilities. Understanding the developmental trajectory of these seemingly interrelated processes is important as both early vocabulary and EF have been shown to predict critical academic and socio-emotional…

Newborns are able to neurally discriminate between speech and nonspeech right after birth. To date it remains unknown whether this early speech discrimination and the underlying neural language network is associated with later language development. Preterm-born children are an interesting cohort to investigate this relationship, as previous…

This study examines the links between urbanization-related factors (crowding, access to institutions, and socioeconomic status) and cognitive development in young children (3-5 years old) in Bhutan, a rapidly urbanizing country in the Global South. Using Structural Equation Modeling (SEM) on data from 443 families, we find that SES is the…

The development of human abilities stems from a complex interplay between genetic predispositions and environmental factors. Numerous studies have compared musicians with non-musicians on measures of musical and non-musical ability, frequently attributing musicians' superior performance to their training. By ignoring preexisting differences,…

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…

Caregivers play an outsized role in shaping early life experiences and development, but we often lack mechanistic insight into "how" exactly caregiver behavior scaffolds the neurodevelopment of specific learning processes. Here, we capitalized on the fact that caregivers differ in how predictable their behavior is to ask if infants'…

Infants undergo fundamental shifts in perception that are reported to be critical for language acquisition. In particular, infants' perception of native and non-native sounds begins to align with the properties of their native sound system. Thus far, empirical evidence for this transition--perceptual narrowing--has drawn from socio-economically…