Around their first birthdays, infants begin to point, walk, and talk. These abilities are appreciable both by researchers with strictly standardized criteria and caregivers with more relaxed notions of what each of these skills entails. Here, we compare the onsets of these skills and links among them across two data collection methods: observation…

Toddlerhood is marked by advances in several lexico-semantic skills, including improvements in the size and structure of the lexicon and increased efficiency in lexical processing. This project seeks to delineate how early changes in vocabulary size and vocabulary structure support lexical processing (Experiment 1), and how these three skills…

Previous research has shown that home environment plays an important role in children's early language skills. Yet, few researchers have examined the unique role of family-level factors (socioeconomic status [SES], household chaos) on children's learning or focused on the longitudinal processes that might explain their relations to children's…

We compared language comprehension and production across the second year of life in children of clinically depressed mothers who later remitted with children of nondepressed mothers. Altogether, 157 mother-child dyads participated: 46 with mothers diagnosed at infant age 5 months as having major, minor, or other depressive disorders who fully…

Adult humans process communicative interactions by recognizing that information is being communicated through speech (linguistic ability) and simultaneously evaluating how to respond appropriately (social-pragmatic ability). These abilities may originate in infancy. Infants understand how speech communicates in social interactions, helping them…

Several theories of executive function (EF) propose that EF development corresponds to children's ability to form representations and reflect on represented stimuli in the environment. However, research on early EF is primarily conducted with preschoolers, despite the fact that important developments in representation (e.g., language, gesture,…

Young children who hear more child-directed speech (CDS) tend to have larger vocabularies later in childhood, but the specific characteristics of CDS underlying this link are currently underspecified. The present study sought to elucidate how the structure of language input boosts learning by investigating whether repetition of object labels in…

A community sample of 192 parents reported on their children's restricted and repetitive behaviors (RRBs) at mean ages 15 months (N = 138), 26 months (N = 191), and 77 months (N = 125) using the Repetitive Behavior Questionnaire-2 (RBQ-2). Consistent with previous factor analytic research, 2 factors were found at each age: 1 comprising repetitive…

The present studies examined the role of linguistic experience in directing English and Mandarin learners' attention to aspects of a visual scene. Specifically, they asked whether young language learners in these 2 cultures attend to differential aspects of a word-learning situation. Two groups of English and Mandarin learners, 6-8-month-olds (n =…

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…

When children hear a novel word in a context presenting a novel object and a familiar one, they usually assume that the novel word refers to the novel object. In a series of experiments, we tested whether this behavior would be found when 2-year-olds interpreted novel words that differed phonologically from familiar words in only 1 sound, either a…

The development of imitation during the second year of life plays an important role in domains of sociocognitive development such as language and social learning. Deficits in imitation ability in persons with autism spectrum disorder (ASD) from toddlerhood into adulthood have also been repeatedly documented, raising the possibility that early…

We longitudinally investigated parental language context and infants' language experiences in relation to Dominican American and Mexican American infants' vocabularies. Mothers provided information on parental language context, comprising measures of parents' language background (i.e., childhood language) and current language use during interviews…

Although there has been much debate over the content of children's first words, few large sample studies address this question for children at the very earliest stages of word learning. The authors report data from comparable samples of 265 English-, 336 Putonghua- (Mandarin), and 369 Cantonese-speaking 8- to 16-month-old infants whose caregivers…