Both classic thought experiments and recent empirical evidence suggest that children frequently encounter new words whose meanings are underdetermined by the extralinguistic contexts in which they occur. The role that these referentially ambiguous events play in children's word learning is central to ongoing debates in the field. Do children learn…

Children can acquire novel word meanings by using pragmatic cues. However, previous literature has frequently focused on in-the-moment word-to-meaning mappings, not delayed retention of novel vocabulary. Here, we examine how children use pragmatics as they learn and retain novel words. Thirty-three younger children (mean age: 5.0, range: 4.0-6.0,…

Purpose: The purpose of this study was to determine if the Vocabulary Acquisition and Usage for Late Talkers (VAULT) intervention could be efficaciously applied to a new treatment target: words a child neither understood nor said. We also assessed whether the type of context variability used to encourage semantic learning (i.e., action or object)…

The fast pace and relative ease at which individuals with typical language acquire and use words belie the complexity and vulnerability of lexical representation development (i.e., word learning) and lexical-semantic processing. Lexical-semantic processing impairments are common in both developmental and acquired communication disorders and, even…

This study investigates the impact of structured vocabulary review on vocabulary acquisition among middle-grade students (grades 6-8) using an experimental, parallel design. Twenty-four classrooms (310 students) were randomly assigned to review different sets of academic vocabulary. Students completed 20 weeks of the Word Generation curriculum,…

Like verbs, adjectives pose a challenge to the young word learner in that some -- like "red," "round," "rough," or "rectangular" -- map onto properties that are detectable through the senses, while others -- like "ready," "reasonable," or "required" -- express abstract…

The present study complemented the extant second language (L2) Age of Acquisition (AoA) normative database by providing over 3500 English L2 words on objective AoA and over 2600 English L2 words on subjective AoA. The correlation between the objective and subjective L2 AoA confirmed the validity of the present database. The objective L2 AoA was…

The account that word learning starts in earnest during the second year of life, when infants have mastered the disambiguation skills, has recently been challenged by evidence that infants during the first year already know many common words. The preliminary ability to rapidly map and disambiguate linguistic labels was tested in Italian-speaking…

Words have meanings vastly undetermined by the contexts in which they occur. Their acquisition therefore presents formidable problems of induction. Lila Gleitman and colleagues have advocated for one part of a solution: indirect evidence for a word's meaning may come from its syntactic distribution, via syntactic bootstrapping. But while formal…

What is vision's role in driving early word production? To answer this, we assessed parent-report vocabulary questionnaires administered to congenitally blind children (N = 40, Mean age = 24 months [R: 7-57 months]) and compared the size and contents of their productive vocabulary to those of a large normative sample of sighted children (N =…

This dissertation articulates and defends a view about linguistic competence called 'variabilism'. According to variabilism, the epistemic demands of full linguistic competence vary in a particular way. More specifically, variabilism holds that different individual lexical application conditions (individually essential metaphysical ways of being…

Recent years have seen a flourishing of Natural Language Processing models that can mimic many aspects of human language fluency. These models harness a simple, decades-old idea: It is possible to learn a lot about word meanings just from exposure to language, because words similar in meaning are used in language in similar ways. The successes of…

Purpose: Late talkers (LTs) are a group of children who exhibit delays in language development without a known cause. Although a hallmark of LTs is a reduced expressive vocabulary, little is known about LTs' processing of semantic relations among words in their emerging vocabularies. This study uses an eye-tracking task to compare 2-year-old LTs'…

Young children can exploit the syntactic context of a novel word to narrow down its probable meaning. This is "syntactic bootstrapping." A learner that uses syntactic bootstrapping to foster lexical acquisition must first have identified the semantic information that a syntactic context provides. Based on the "semantic seed…

Many children with developmental language disorder (DLD) have a vocabulary deficit. One of the most effective interventions for increasing children's lexicon size is the semantic and phonological approach, an approach that has been used mainly with adolescents. The goals of our study are (1) to test whether the semantic-phonological approach…