A critical question in the study of language development is to understand lexical and syntactic acquisition, which play different roles in speech to the extent it would be natural to surmise they are acquired differently. As measured through the comprehension and production of closed-class words, syntactic ability emerges at roughly the 400-word…

In this study, infant vocabulary development was tracked in a multilingual society (Singapore) within a socioeconomically diverse sample. The sample comprised 1316 infants from 17.4 to 27.7 months (669 females, 647 males; 88% Chinese race, 4% Malay, 4% Indian, and 0.004% mixed-race [4% declined to provide race information]). Children varied in…

Lexical iconicity--signs or words that resemble their meaning--is overrepresented in children's early vocabularies. Embodied theories of language acquisition predict that symbols are more learnable when they are grounded in a child's firsthand experiences. As such, pantomimic iconic signs, which use the signer's body to represent a body, might be…

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…

Toddlerhood is marked by advances in several lexico-semantic skills, including improvements in the size and structure of the lexicon and increased efficiency in lexical processing. This project seeks to delineate how early changes in vocabulary size and vocabulary structure support lexical processing (Experiment 1), and how these three skills…

One of the most popular and widely used parent report instruments for assessing early language acquisition is the MacArthur-Bates Communicative Development Inventories (MB-CDI). This study compares normative data of the Italian Words and Sentences complete form (WS-CF) and short form (WS-SF). The samples included 752 children for the WS-CF and 816…

Purpose: This study examined the efficacy of the Vocabulary Acquisition and Usage for Late Talkers (VAULT) treatment in a version that manipulated the length of clinician utterance in which a target word was presented (dose length). The study also explored ways to characterize treatment responders versus nonresponders. Method: Nineteen primarily…

Purpose: This study examined vocabulary profiles in young cochlear implant (CI) recipients and in children with normal hearing (NH) matched on receptive vocabulary size to improve our understanding of young CI recipients' acquisition of word categories (e.g., common nouns or closed-class words). Method: We compared receptive and expressive…

The relationship between first and second language in early vocabulary acquisition in bilingual children is still debated in the literature. This study compared the expressive vocabulary of 39 equivalently low-SES two-year-old bilingual children from immigrant families with different heritage languages (Romanian vs. Nigerian English) and the same…

This article presents data on lexical development of 881 Israeli Hebrew-speaking monolingual toddlers ages 1;0 to 2;0. A Web-based version of the Hebrew MacArthur-Bates Communicative Development Inventories (H-MB-CDI) was used for data collection. Growth curves for expressive vocabulary, receptive vocabulary, actions and gestures were…

The focus of this article is Faroese children's early vocabulary acquisition using a Faroese adaptation of the MacArthur-Bates Communicative Development Inventories (MBCDI) parental report. The study is a population-based cross-sectional study including 1135 children aged 8-36 months. The article has two objectives: the first is to describe the…

Purpose: We report on a replicated single-case design study that measured the feasibility of an expressive vocabulary intervention for three Cantonese-speaking toddlers with small expressive lexicons relative to their age. The aim was to assess the cross-cultural and cross-linguistic feasibility of an intervention method developed for…

Previous research indicates that infant-directed speech (IDS) is usually slower than adult-directed speech (ADS) and mothers prefer placing a focused word in isolation or utterance-final position in (English) IDS, which may benefit word learning. This study investigated the speaking rate and word position of IDS in two typologically-distinct…

This study examined longitudinal growth in gestures and words in infants at heightened (HR) versus low risk (LR) for ASD. The MacArthur-Bates Communicative Development Inventory was administered monthly from 8 to 14 months and at 18 and 24 months to caregivers of 14 HR infants diagnosed with ASD (HR-ASD), 27 HR infants with language delay (HR-LD),…

Assessing a child's language in the early years is critical to plan for an early intervention and maximize their learning potential. In a unique pan-Arabic approach to language development, we developed a new Arabic assessment tool, usable by parents and Early Years professionals to screen vocabulary in children between 8 months and 30 months…