Codeswitching is a common feature of bilingual language practices, yet its impact on word learning is poorly understood. Critically, processing costs associated with codeswitching may extend to learning. Moreover, verbs tend to be more difficult to learn than nouns, and the challenges of learning verbs could compound with processing costs…

Early vocabulary development benefits from diverse lexical exposures within children's language environment. However, the influence of lexical diversity on children as they enter middle childhood and are exposed to multimodal language inputs remains unclear. This study evaluates global and local aspects of lexical diversity in three…

Children need to learn the demands of their native language in the early vocabulary development phase. In this dynamic process, parental multimodal input may shape neurodevelopmental trajectories while also being tailored by child-related factors. Moving beyond typically characterized group profiles, in this article, we synthesize growing evidence…

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…

While it is established that parental "wh"-questions, as a high-quality language input, are associated with child language outcome, less is known about the role of children's "wh"-questions in their language development. This study examines whether children's "wh"-questions during a dinnertime conversation are…

The Mayan language Mam uses complex predicates to express events. Complex predicates map multiple semantic elements onto a single word, and consequently have a blend of lexical and phrasal features. The chameleon-like nature of complex predicates provides a window on children's ability to express phrasal combinations at the one-word stage of…

Toddlers with smaller vocabulary than expected for their age are considered late talkers (LT). This study explored the effects of characteristics of words on vocabulary acquisition of 12- to 24-month-old LT children compared with an age matched (AM) and a vocabulary matched (VM) group of typically developing peers. Using the…

Young children's language skills have a significant positive impact on their academic success throughout school, especially on reading and writing performance. The spread of COVID-19, which has resulted in lockdowns, fewer learning hours in kindergarten, and distance learning, might have affected children's exposure to learning opportunities. The…

Research on "parentese," the acoustically exaggerated, slower, and higher-pitched speech directed toward infants, has mostly focused on maternal contributions, although it has long been known that fathers also produce parentese. Given recent societal changes in family dynamics, it is necessary to revise these mother-centered models of…

One of the fundamental questions in the field of language acquisition is a learnability problem, which considers how learners acquire certain aspects of language which are not directly provided in the input or whose referents are not readily observable. This dissertation investigates Japanese children's acquisition of various linguistic phenomena,…

Research Findings: Early childhood teachers' talk is a key ingredient in children's early language and literacy development, but there has been little systematic synthesis of observational studies that examine relationships between teacher talk and child oral language. In this systematic review of 54 studies, we investigate and synthesize the…

Collocations, e.g., apples and pears, hard worker, constitute an important avenue of linguistic enquiry straddling both grammar and the lexicon. They are sensitive to language experience, with adult L2 learners and children learning English as an Additional Language (EAL) exhibiting poor collocational knowledge. The current study piloted a novel…

Do mono- and bilingual children differ in the way they learn novel words in ambiguous settings? Listeners may resolve referential ambiguity by assuming that novel words refer to unknown, rather than known, objects--a response known as the "mutual exclusivity effect." Past research suggested that mono- and bilinguals differ with regard to…

Research Findings: The present study investigates both the proximal processes and contextual influences on children's oral language development in preschool. We examine whether teacher language practices vary across activity settings and program type, which teacher language practices predict children's oral language skills, and potential…

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…