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…

Purpose: Talkers adapt their speech according to the demands of their listeners and the communicative context, enhancing the properties of the signal (pitch, intensity) and/or properties of the code (enhancement of phonemic contrasts). This study asked how mothers adapt their child-directed speech (CDS) in ways that might serve the immediate goals…

This study focuses on parental use of parentese: the acoustically exaggerated, clear, and higher-pitched speech produced by adults across cultures when they address infants. While previous research shows that parentese enhances language learning and processing, it is still unclear what drives the variability in the amount of parental parentese…

Children need to learn the demands of their native language in the early vocabulary development phase. In this dynamic process, parental multimodal input may shape neurodevelopmental trajectories while also being tailored by child-related factors. Moving beyond typically characterized group profiles, in this article, we synthesize growing evidence…

High-quality communicative interactions between caregivers and children provide a foundation for children's social and cognitive skills. Although most studies examining these types of interactions focus on child language outcomes, this paper takes another tack. It examines whether communicative, dyadic interactions might also relate to child…

Having heard "a pimwit", English-speakers assume that "the pimwit" is also possible. This type of productivity is attributed to syntactic categories such as NOUN and DETERMINER, but the key question is "how" do humans become endowed with these categories in the first place. We propose a novel approach that combines…

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…

Both the amount "and" responsiveness of adult language input contribute to the language development of autistic and non-autistic children. From parent-child interaction footage, we measured the amount of adult language input, overall parent responsiveness, and six discrete parent responsive behaviours ("imitations, expansions,…

Child-directed language can support language learning, but how? We addressed two questions: (1) how caregivers prosodically modulated their speech as a function of word familiarity (known or unknown to the child) and accessibility of referent (visually present or absent from the immediate environment); (2) whether such modulations affect…

Children learn math concepts long before they enter school. Across all cultures, children are exposed to number and spatial language to varying degrees during everyday home routines. Yet most studies of math talk occur in the lab and target non-Hispanic, English-speaking families. We expanded inquiry to the spontaneous math language (i.e., number…

Background: Parental input plays a central role in typical language acquisition and development. In autism spectrum disorder (ASD), characterized by social communicative and language difficulties, parental input presents an important avenue for investigation as a target for intervention. A rich body of literature has identified which aspects of…

Purpose: This study aims to examine the development of auditory selective attention to speech in noise by examining the ability of infants to prefer child-directed speech (CDS) over time-reversed speech (TRS) presented in "on-channel" and "off-channel" noise. Method: A total of 32 infants participated in the study. Sixteen…

To address the variability of naturalistic developmental behavioral intervention outcomes, the current study sought to isolate the effects of the instructional strategies of caregiver-mediated naturalistic developmental behavioral interventions. In this comparative efficacy trial, mothers of 111 autistic children (18-48 months) were randomized to…

This qualitative ethnographic research explores baby talk (BT) and ontology of infancy in a small, rural Indo-Fijian community via semistructured interviews with mothers about their children's language learning, mothers' narratives about their photographs of their young children engaged in everyday language, and audio- and video-recordings of…

Children acquire language embedded within the rich social context of interaction. This paper reports on a longitudinal study investigating the developmental relationship between conversational turn-taking and vocabulary growth in English-acquiring children (N = 122) followed between 9 and 24 months. Daylong audio recordings obtained every 3 months…