Children with autism spectrum disorder often have significant language delays. But do they learn language differently than neurotypical toddlers? We compared the lexical skills of 64 preverbal and minimally verbal children with autism spectrum disorder to 461 vocabulary-size-matched typically developing toddlers. We also examined social features…

Vocabulary checklists completed by caregivers are a common way of measuring children's vocabulary knowledge. We provide evidence from checklist data from 31 children with and without autism spectrum disorder. When asked to report twice about whether or not their child produces a particular word, caregivers are largely consistent in their…

Purpose: We examined receptive verb knowledge in 22- to 24-month-old toddlers with a dynamic video eye-tracking test. The primary goal of the study was to examine the utility of eye-gaze measures that are commonly used to study noun knowledge for studying verb knowledge. Method: Forty typically developing toddlers participated. They viewed 2…

Purpose: The study examined the effects of imageability and phonological neighborhood density on the acquisition of word production in Czech, controlling for part-of-speech class, word length, and word frequency. Phonological neighborhood density is of interest because previous research has not examined highly inflected languages such as Czech.…

Parent input during interaction with young children varies across languages and contexts with regard to the relative number of words from different lexical categories, particularly nouns and verbs. Previous work has focused on spoken language input. Little is known about the lexical composition of parent input in American Sign Language (ASL). We…

Linguistic contexts provide useful information about verb meanings by narrowing the space of candidate concepts. Intuitively, the more information, the better. For example, "the tall girl is 'fezzing,'" as compared to "the girl is fezzing," provides more information about which event, out of multiple candidate events, is being…

Children's lexical processing speed at 18 to 25 months of age has been linked to concurrent and later language abilities. In the current study, we extend this finding to children aged 36 months. Children (N = 126) participated in a lexical processing task in which they viewed two static images on noun trials (e.g., an ear of corn and a hat), or…

Purpose: We examined receptive verb knowledge in 22- to 24-month-old toddlers with a dynamic video eye-tracking test. The primary goal of the study was to examine the utility of eye-gaze measures that are commonly used to study noun knowledge for studying verb knowledge. Method: Forty typically developing toddlers participated. They viewed 2…

Purpose: The goals of this study were to quantify longitudinal expectations for verb lexicon growth and to determine whether verb lexicon measures were better predictors of later grammatical outcomes than noun lexicon measures. Method: Longitudinal parent-report measures from the MacArthur-Bates Communicative Development Inventory (Fenson et al.,…

This mixed two-way experimental, cross-sectional study investigated fast-mapping (FM) of novel nouns and verbs in 63 Persian-speaking toddlers aged 30 months, including 31 late-talking (LT) and 32 typically developing (TD) matched with respect to age and maternal education. Toddlers were classified as LT if they had limited expressive vocabulary…

This cross-sectional study investigated the use of four verbal indices of social knowledge (personal pronouns, verb conjugations, people words and mental state language) and their concurrent relations in a sample of 287 Italian-speaking children between 18 and 36 months. Results showed that the production of all indices increased with age. Mental…

Purpose: This experiment examined English- or Spanish-learning preverbal (8-9 months, n = 32) and postverbal (12-14 months, n = 40) infants' learning of word-action pairings prior to and after the transition to verb comprehension and its relation to naturally learned vocabulary. Method: Infants of both verbal levels were first habituated to 2…

The purpose of this study was to understand vocabulary characteristics in toddlers who are late talkers (LT) as compared with age-matched (AM) and vocabulary-matched (VM) peers. The semantic categories (e.g., animals, foods, toys) and the percentage of nouns, verbs, and closed-class words in the vocabularies of 36 toddlers (12 LT, 12 AM, 12 VM)…

Syntactic bootstrapping facilitates children's initial learning of verb meanings based on syntactic information. A challenging case is the argument-drop languages, where the number of argument NPs is not a reliable cue for distinguishing between transitive and intransitive verbs. Despite this fact, the availability of syntactic bootstrapping in…

The present study examined continuity/discontinuity and stability/instability of noun and verb production measures in 30 child-mother dyads observed at 16 and 20 months, and predictive relations with the acquisition of nouns and verbs at 24 months. Children exhibited significant discontinuity and robust stability in the frequency of nouns and…