Previous research shows that infants of parents who are more likely to engage in socially contingent interactions with them tend to have larger vocabularies. An open question is "how" social contingency facilitates vocabulary growth. One possibility is that parents who speak in response to their infants more often produce larger…

Prior research points to gender differences in some early language skills, but is inconclusive about the mechanisms at play, providing evidence that both infants' early input and productions may differ by gender. This study examined the linguistic input and early productions of 44 American English-learning infants (93% White) in a longitudinal…

The present study examined patterns of number-related utterances and actions directed to 9-month-old infants by their parents. An ethnically and economically diverse sample of 86 families participated in structured play sessions conducted separately with the mothers and fathers of each infant. Data were coded for eight math talk categories, and…

The current study examined the inter-brain coherence (IBC) between 34 dyads of fathers and infants 7-9 months of age using functional near-infrared spectroscopy (fNIRS). We specifically focused on father-infant IBC to broaden the empirical base beyond the mother-infant connections, as the former has received limited attention. There were three…

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…

There is a great deal of variability in how families read and interact with picture books. To understand why reading practices may (or may not) relate to language outcomes, a necessary step to understand what occurs in the home. The goal of this work is to better understand the frequency and nature of picture book reading at home with children…

COVID-19 has modified numerous aspects of children's social environments. Many children are now spoken to through a mask. There is little empirical evidence attesting to the effects of masked language input on language processing. In addition, not much is known about the effects of clear masks (i.e., transparent face shields) versus opaque masks…

Bilingualism is a powerful experiential factor, and its effects have been proposed to extend beyond the linguistic domain by boosting the development of executive functioning skills. Crucially, recent findings suggest that this effect can be detected in bilingual infants before their first birthday indicating that it emerges as a result of early…

Infants are immersed in a world of sounds from the moment their auditory system becomes functional, and experience with the auditory world shapes how their brain processes sounds in their environment. Across cultures, speech and music are two dominant auditory signals in infants' daily lives. Decades of research have repeatedly shown that both…

For the past 25 years, researchers have investigated language input to children from high- and low-socioeconomic status (SES) families. Hart and Risley first reported a "30 Million Word Gap" between high-SES and low-SES children. More recent studies have challenged the size or even existence of this gap. The present study is a…

New motor skills supply infants with new possibilities for action and have consequences for development in unexpected places. For example, the transition from crawling to walking is accompanied by gains in other abilities--better ways to move, see the world, and engage in social interactions (e.g., Adolph & Tamis-LeMonda, 2014). Do the…

Why do infants learn some words earlier than others? Many theories of early word learning focus on explaining how infants map labels onto concrete objects. However, words that are more abstract than object nouns, such as "uh-oh," "hi," "more," "up," and "all-gone," are typically among the first to…

Background: Although language difficulties are one of the most distinctive characteristics of the neuropsychological profile of children with sex chromosome trisomies (SCT), the analysis of the maternal input addressed to them is a neglected topic. Aims: The present study aims to analyse the lexical, morphosyntactic, and functional features of the…

Examining how bilingual infants experience their dual language input is important for understanding bilingual language acquisition. To assess these language experiences, researchers typically conduct language interviews with caregivers. However, little is known about the reliability of these parent reports in describing how bilingual children…

A selective literature review by Hall and Dills ([2020]. The Limits of "Communication Mode" as a Construct. "Journal of Deaf Studies and Deaf Education.") (EJ1273461) recently argued that limitations in communication mode as a construct prevent empirical research from discovering what type(s) of early language input optimise…