Children learn language by listening to speech from caregivers around them. However, the type and quantity of speech input that children are exposed to change throughout early childhood in ways that are poorly understood due to the small samples (few participants, limited hours of observation) typically available in developmental psychology. Here…

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…

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…

Spoken language outcomes after cochlear implantation are highly variable. Some variance can be attributed to individual characteristics. Research with typically hearing children suggests that the amount of language directed to children may also play a role. However, several moderating factors may complicate the association between language input…

Despite the fact that in most communities interaction occurs between the child and multiple speakers, most previous research on input to children focused on input from mothers. We annotated recordings of Sesotho-learning toddlers living in non-industrial Lesotho in South Africa, and French-learning toddlers living in urban regions in France. We…

The linguistic input children receive across early childhood plays a crucial role in shaping their knowledge about the world. To study this input, researchers have begun applying distributional semantic models to large corpora of child-directed speech, extracting various patterns of word use/co-occurrence. Previous work using these models has not…

Early linguistic environment has shown an impact on children's later language development, particularly, child directed speech has been associated with providing children with linguistic input from which to look for regularities and patterns, and boosting children to produce utterances beyond their current competence. This article aims to examine…

How early do children produce multiword utterances? Do children's early utterances reflect abstract syntactic knowledge or are they the result of data-driven learning? We examine this issue through corpus analysis, computational modeling, and adult simulation experiments. Chapter 1 investigates when children start producing multiword utterances;…

Interventions focused on the home language environment have been shown to improve a number of child language outcomes in the first years of life. However, data on the longer-term effects of the intervention are still somewhat limited. The current study examines child vocabulary and complex speech outcomes (N = 59) during the year following…

Parents are often a good source of information, introducing children to how the world around them is described and explained in terms of cause-and-effect relations. Parents also vary in their speech, and these variations can predict children's later language skills. Being born preterm might be related to such parent-child interactions. The present…

We trained a computational model (the Chunk-Based Learner; CBL) on a longitudinal corpus of child-caregiver interactions in English to test whether one proposed statistical learning mechanism--backward transitional probability--is able to predict children's speech productions with stable accuracy throughout the first few years of development. We…

It is known that the rhythms of speech are visible on the face, accurately mirroring changes in the vocal tract. These low-frequency visual temporal movements are tightly correlated with speech output, and both visual speech (e.g., mouth motion) and the acoustic speech amplitude envelope entrain neural oscillations. Low-frequency visual temporal…

Children's daily contexts shape their experiences. In this study, we assessed whether variations in infant placement (e.g., held, bouncy seat) are associated with infants' exposure to adult speech. Using repeated survey sampling of mothers and continuous audio recordings, we tested whether the use of independence-supporting placements was…

This dissertation investigates the wide-ranging implications of a simple fact: language unfolds over time. Whether as cognitive symbols in our minds, or as their physical realization in the world, if linguistic computations are not made over transient and shifting information as it occurs, they cannot be made at all. This dissertation explores the…

Understanding how a child's language system develops into an adult-like system is a central question in language development research. An increasingly influential account proposes that the brain constantly generates top-down predictions and matches them against incoming input, with higher-level cognitive models serving to minimize prediction…