While much work has emphasized the role of the environment in language learning, research equally reports consistent effects of the child's knowledge, in particular, the words known to individual children, in steering further lexical development. Much of this work is based on cross-sectional data, assuming that the words typically known to…

This study is a validation of the LENA system for the Italian language. In Study 1, to test LENA's accuracy, seventy-two 10-minute samples extracted from daylong LENA recordings were manually transcribed for 12 children longitudinally observed at 1;0 and 2;0. We found strong correlations between LENA and human estimates in the number of Adult Word…

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…

This study investigated the developmental pattern of early lexical production and composition in Mandarin-speaking children. Forty Mandarin-speaking children and their parents participated in this one-and-a-half-year longitudinal study, and naturalistic samples of parent-to-child speech in toy play were collected when the children were 1;8, 2;2,…

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…

Purpose: This study examines the expressive language and speech of twins, relative to singletons, at 3 and 5 years, with the aim of determining if a twinning effect occurs during this developmental period. The possibility of twins outgrowing a twinning effect was investigated. Method: A weighted population-based sample of 185 twins and 1,309…

Individuals with sex chromosome trisomies (SCTs) have an increased risk of language delays and impairments. However, there are only a few data relative to their language development in early childhood. The present study aimed to investigate the preverbal skills shown by a group of 8-month-old children with SCTs to assess the presence of a possible…

Background: Early intervention for children identified as late talkers (LTs) at the age of 24 months is still a controversial issue in research and clinical routine. Previous studies have shown inconsistent results regarding predictors of early lexical deficits on school-age outcomes of late-talking toddlers. Methods: In a five-wave follow-up…

The number of unique words in children's speech is one of most basic statistics indicating their language development. We may, however, face difficulties when trying to accurately evaluate the number of unique words in a child's growing corpus over time with a limited sample size. This study proposes a novel technique to estimate the latent number…

This study investigated the relation between lexical development and the production of prosodic prominence in disyllabic babble and words. Monthly recordings from nine typically developing Belgian-Dutch-speaking infants were analyzed from the onset of babbling until a cumulative vocabulary of 200 words was reached. The differentiation between the…

Infants from low-socioeconomic status (SES) households hear a projected 30 million fewer words than their higher-SES peers. In a recent study, Hirsh-Pasek et al. (Psychological Science, 2015; 26: 1071) found that in a low-income sample, fluency and connectedness in exchanges between caregivers and toddlers predicted child language a year later…

Background: Late language emergence is a risk indicator for developmental language disorder. Parent-implemented early language intervention programmes (parent programmes) have been shown to have positive effects on children's receptive and expressive language skills. However, long-term effectiveness has rarely been studied. Additionally, little is…

This study employs the Specificity Principle to examine the relative impacts of external (input quantity at home and at school, number of books and reading frequency at home, teachers' degree and experience, language usage, socioeconomic status) and internal factors (children's working memory, nonverbal intelligence, learning-related…

Recent studies demonstrate that emerging literacy depends on earlier language achievement. Importantly, most extant work focuses on "parent-reported production" prior to 30 months of age. Of interest is whether and how "directly assessed vocabulary comprehension" in the 2nd year of life supports vocabulary and kindergarten…

Using multi-level growth modeling, we examined the effect of several measures of maternal input on growth in children's word types from 15-54 months. Mothers and children engaged in a picture description task (N = 77) at 15, 24, 33, and 54 months; the frequency of children's observed word types at each wave was coded and additional independent…