Research on the home literacy environment has typically involved parents as teachers with little attention given to siblings' roles in teaching each other. This study examines naturalistic language and literacy teaching by 39 sibling dyads, at two timepoints, when children were ages 2 and 4 (time 1; T1) and again at ages 4 and 6 (time 2; T2). Each…

Although a bilingual advantage has been reported for various measures of cognitive control, most previous studies have looked at a limited range of cognitive control measures. Furthermore, they typically leave unaddressed whether positive effects of bilingualism hold for all bilinguals or whether these are modulated by differences in bilingual…

This mixed two-way experimental, cross-sectional study investigated fast-mapping (FM) of novel nouns and verbs in 63 Persian-speaking toddlers aged 30 months, including 31 late-talking (LT) and 32 typically developing (TD) matched with respect to age and maternal education. Toddlers were classified as LT if they had limited expressive vocabulary…

Approximately 10% of children with a speech sound disorder present with an inconsistent phonological disorder, characterized by inconsistent production of words across multiple trials. A number of studies have provided evidence of the efficacy of core vocabulary therapy for the remediation of this speech sound disorder with a dosage of two…

Some children enter elementary school with large vocabulary delays, which negatively influence their later school performance. A rich home language environment can support vocabulary development through frequent high-quality parent-toddler interaction. Elaborated picture home activities can support this rich home language environment. This study…

By their second birthday, children have begun using grammatical cues to decipher the meaning of newly encountered words. By 3 years of age, there is evidence that children are more reliant on grammatical than social cues to decipher verb meaning (Nappa, Wessel, McEldoon, Gleitman, & Trueswell, 2009). Here, we investigate children's reliance on…

Both the input directed to the child, and the child's ability to process that input, are likely to impact the child's language acquisition. We explore how these factors inter-relate by tracking the relationships among: (a) lexical properties of maternal child-directed speech to prelinguistic (7-month-old) infants (N = 121); (b) these infants'…

There are clear associations between the overall quantity of input children are exposed to and their vocabulary acquisition. However, by uncovering specific features of the input that matter, we can better understand the mechanisms involved in vocabulary learning. We examine whether exposure to "wh"-questions, a challenging quality of…

The aim of this longitudinal study, carried out on a sample of Slovenian-speaking toddlers, was to analyze developmental changes and stability in early vocabulary development; to establish relations between toddler's vocabulary and grammar; and to analyze the effects of parental education and the frequency of shared reading on toddlers' vocabulary…

Although research suggests that responsive interactions are imperative for language development, the advent of mobile technology means that parent-child exchanges are often fraught with unpredictable interruptions. Less clear is how these momentary breaks in responsiveness affect word learning. In this within-subjects design, 38 mothers taught…

In some areas of rural Africa, long-standing cultural traditions and beliefs may discourage parents from verbally engaging with their young children. This study assessed the effectiveness of a parenting program designed to encourage verbal engagement between caregivers and infants in Wolof-speaking villages in rural Senegal. Caregivers (n = 443)…

Cumulative vocabulary models for infants and toddlers were developed from models of learning that predict trajectories associated with low, average, and high vocabulary growth rates (14 to 46 months). It was hypothesized that models derived from rates of learning mirror the type of exchanges provided to infants and toddlers by parents and…

Both early childhood maternal language input and the quality of classroom instruction in elementary school have been shown to be important environmental supports in predicting children's literacy skill development. However, no studies have simultaneously examined these two environmental supports in relation to children's early language skills and…

The results from a large-scale study on toddlers' language acquisition in European Portuguese are presented. Toddlers' lexical and grammatical competencies were assessed using the MacArthur-Bates Communicative Development Inventory: Words and Sentences. The results, based on 3012 reports completed by parents, indicate an increase in the lexical…

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…