Psycholinguistic research on children's early language environments has revealed many potential challenges for language acquisition. One is that in many cases, referents of linguistic expressions are hard to identify without prior knowledge of the language. Likewise, the speech signal itself varies substantially in clarity, with some productions…

Infants' sensitivity to transitional probabilities (TPs) supports language development by facilitating mapping high-TP (HTP) words to meaning, at least up to 18 months of age. Here we tested whether this HTP advantage holds as lexical development progresses, and infants become better at forming word--referent mappings. Two groups of 24-month-olds…

This dissertation presents behavioral studies that target the early syntactic representations of "wh"-movement during infancy and early childhood. Previous studies show that by 20 months-old, infants represent "wh"-movement and use this knowledge to respond to "wh"-questions during language comprehension tasks…

Children comprehend iconic gestures relatively later than deictic gestures. Previous research with English-learning children indicated that they could comprehend iconic gestures at 26 months, a pattern whose extension to other languages is not yet known. The present study examined Turkish-learning children's iconic gesture comprehension and its…

Words that describe sensory perception give insight into how language mediates human experience, and the acquisition of these words is one way to examine how we learn to categorize and communicate sensation. We examine the differential predictions of the typological prevalence hypothesis and embodiment hypothesis regarding the acquisition of…

This study examined joint engagement, parent labels, and language development in infants with an elevated (EL) and typical likelihood (TL) for ASD. Parent-child interactions were coded for joint engagement and parent labels at 12 and 18 months, and language skills were assessed later in toddlerhood for 12 EL infants diagnosed with ASD (EL-ASD), 17…

Most deaf children have hearing parents who do not know a sign language at birth and are at risk of limited language input during early childhood. Studying these children as they learn a sign language has revealed that timing of first-language exposure critically shapes language outcomes. But the input deaf children receive in their first language…

This article explores the applicability of mean length of utterance (MLU) as a language assessment measure for Georgian child language, as to-date, Georgian, a morphologically rich language with numerous inflectional categories, experiences an extensive lack of instruments for early language assessment. To this end, a set of guidelines for…

Children's vocabulary ability at school entry is highly variable and predictive of later language and literacy outcomes. Sleep is potentially useful in understanding and explaining that variability, with sleep patterns being predictive of global trajectories of language acquisition. Here, we looked to replicate and extend these findings. Data from…

This article evaluates the acquisition of directionals in Q'anjob'al, a Western Mayan language of Guatemala. The data come from a longitudinal study of two Q'anjob'al monolingual children of Santa Eulalia, Huehuetenango, Guatemala: Xhuw (1;9-2;5) and Xhim (2;3-3;5). The results show how these children acquire the morphological distribution 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…

Children's ability to recognize object shape is foundational for successful early word learning. However, the prototypical shape of objects may not be easily accessible--take margarita glasses, for instance. The current study examined 304 U.S. children 17- to 42-month-old (152 females) from 2017 to 2020, asking how shape, age, and vocabulary…

Vocabulary size is a crucial early indicator of language development, for both monolingual and bilingual children. Assessing vocabulary in bilingual children is complex because they learn words in two languages, and there remains significant controversy about how to best measure their vocabulary size, especially in relation to monolinguals. This…

Children's speech is influenced by the speech they hear, in particular by the parental speech addressed directly to them. The aim of this study was to analyse toddlers' speech with their parents and to investigate the influence of specific characteristics of child-directed speech on child speech in real time during mother-child and father-child…

Speech problems affect about 66% of children with classic galactosemia (CG), but limited evidence is reported on early motor and sensory motor development in this at-risk population. Research has been focused on speech and language development, leaving a paucity of data on motor and sensory differences. This paper describes preliminary data…