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…

Background: Variability in the vocabulary outcomes of children with cochlear implants (CIs) is partially explained by child-directed speech (CDS) characteristics. Yet, relatively little is known about whether and how mothers adapt their lexical and prosodic characteristics to the child's hearing status (before and after implantation, and compared…

Children comprehend iconic gestures relatively later than deictic gestures. Previous research with English-learning children indicated that they could comprehend iconic gestures at 26 months, a pattern whose extension to other languages is not yet known. The present study examined Turkish-learning children's iconic gesture comprehension and its…

Most deaf children have hearing parents who do not know a sign language at birth and are at risk of limited language input during early childhood. Studying these children as they learn a sign language has revealed that timing of first-language exposure critically shapes language outcomes. But the input deaf children receive in their first language…

Sometime before their second birthday, many children have a period of rapid expressive vocabulary growth called the vocabulary spurt. Theories of the underlying mechanisms differ: Accumulator models emphasize the accumulation of experience with words over time to yield a spurtlike pattern, while cognitive models attribute the spurt to cognitive…

Children's ability to recognize object shape is foundational for successful early word learning. However, the prototypical shape of objects may not be easily accessible--take margarita glasses, for instance. The current study examined 304 U.S. children 17- to 42-month-old (152 females) from 2017 to 2020, asking how shape, age, and vocabulary…

Vocabulary size is a crucial early indicator of language development, for both monolingual and bilingual children. Assessing vocabulary in bilingual children is complex because they learn words in two languages, and there remains significant controversy about how to best measure their vocabulary size, especially in relation to monolinguals. This…

Previous work indicates mutual exclusivity in word learning in monolingual, but not bilingual toddlers. We asked whether this difference indicates distinct conceptual biases, or instead reflects best-guess heuristic use in the absence of context. We altered word-learning contexts by manipulating whether a familiar- or unfamiliar-race speaker…

Potentially serving as the primary national literacy initiative, the Reading Seed Programme (RSP) by PUSTAKA Negeri Sarawak aims to enculturate a reading culture from an early age. For instance, RSP was invented to promote reading culture by having the pregnant mother read to their infant until the child was three years old. The process is vital…

Aims: Although IDS is typically described as slower than adult-directed speech (ADS), potential impacts of slower speech on language development have not been examined. We explored whether IDS speech rates in 42 mother-infant dyads at four time periods predicted children's language outcomes at two years. Method: We correlated IDS speech rate with…

Purpose: This study sought to (a) characterize the demographic, audiological, and intervention variability in a population of Deaf and Hard of Hearing (DHH) children receiving state services for hearing loss; (b) identify predictors of vocabulary delays; and (c) evaluate factors influencing the success and timing of early identification and…

Infants and toddlers experience the world in interaction with others. Likewise, social interactions are important in learning about math--concepts of number ("one," "two," "three"), space ("on top," "upside-down," "round"), and magnitude ("more," "big,"…

This study investigates the influence of semantic maturation on early lexical development by examining the impact of contextual diversity--known to influence semantic development--on word promotion from receptive to productive vocabularies (i.e., comprehension-expression gap). Study 1 compares the vocabularies of 3685 American-English-speaking…

In this article, we present an analysis of the complexity of grammatical constraints and their impact on early language acquisition of inflectional morphemes in Malayalam. We use the natural speech production data of two monolingual children acquiring Malayalam between the ages 1;9-2;10 and 2;3-3;0 and three bilingual children acquiring…

Most words spoken to infants are produced in larger units, such as clauses, phrases, and sentences. As such, language learners must recognize words amidst the words that surround them. However, the phonetic forms of words change based on surrounding context. Here, we investigate the effects of a common source of phonetic change--phonological…