Objective: The tendency to vocalize toward objects is ubiquitous among young infants. However, little is known about the range of this tendency and its contribution to language development. Therefore, this longitudinal study objective was to explore the role of three forms of vocal behavior (vocalization, babbling, and speech) directed toward…

Our aim was to assess whether infants influence the quantity and quality of their mothers' speech to them and, in turn, whether this maternal speech influences children's later language. As 189 mothers interacted with each of their twins at age 0;5, we calculated the number of utterances, the proportion of sensitive utterances, and the proportion…

Associations have been observed between socioeconomic status (SES) and language outcomes from early childhood, but individual variability is high. Exposure to high levels of stress, often associated with low-SES status, might influence how parents and infants interact within the early language environment. Differences in these early language…

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…

Individual variability in infant's language processing is partly explained by environmental factors, like the quantity of parental speech input, as well as by infant-specific factors, like speech production. Here, we explore how these factors affect infant word segmentation. We used an artificial language to ensure that only statistical…

Previous studies reveal an association between particular features of parental language input and advances in children's language learning. However, it is not known whether parent coaching aimed to enhance specific input components would (a) successfully increase these components in parents' language input and (b) result in concurrent increases in…

Children use language structures as a basis for learning how to read. Therefore, literacy learning for young children must incorporate the child's personal use of oral language. It is their personal oral language that supports them as they attempt new concepts and become better readers. Because of the important role that oral language plays in a…

Purpose: The aim of this study is to analyze the changes in temporal synchrony between gesture and speech of multimodal communicative behaviors in the transition from babbling to two-word productions. Method: Ten Spanish-speaking children were observed at 9, 12, 15, and 18 months of age in a semistructured play situation. We longitudinally…

Maternal responsive and directive speech to children at ages 0;10 and 2;0 was investigated by applying a procedure frst introduced by Flynn and Masur (2007) to a new language community (Finnish). The issues examined were consistency and stability over time, and also the role of responsiveness and directiveness in child linguistic development at…

Specific developmental concerns can distinguish between an early versus later diagnosis of autism spectrum disorder (ASD). Caregiver survey responses of children = 9 years-of-age (2012) with ASD were used to evaluate developmental concerns and associations with age of diagnosis [early (< 3 years: n = 106) vs. later (= 3 years: n = 432)] using…

This study tested the impact of child-directed language input on language development in Spanish-English bilingual infants (N = 25, 11- and 14-month-olds from the Seattle metropolitan area), across languages and independently for each language, controlling for socioeconomic status. Language input was characterized by social interaction variables,…

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…

Background: Identifying risk and protective factors for language development informs interventions for children with developmental language disorder (DLD). Maternal responsive and intrusive communicative behaviours are associated with language development. Mother-child interaction quality may influence how children use these behaviours in language…

This study analyzes how others engage rural and urban Mozambican infants during naturalistic observations, and how the proportion of time spent in different engagements relates to infants' language development over the second year of life. Using an extended version of Bakeman and Adamson's (1984) categorization of infant engagement, we…

The objective of this study was to investigate changes in the natural language environments of families with typically-developing infants receiving language feedback in South Korea. Volunteer parents of 99 children aged 4-16 months were randomly divided into experimental and control groups. During 6 months' intervention, the experimental group…