During word learning moments, toddlers experience labels and objects in particular environments. Do toddlers learn words better when the physical environment creates contrasts between objects with different labels? Thirty-six 21- to 24-month-olds (92% White, 22 female, data collected 8/21-4/22) learned novel words for novel objects presented using…

How does one assess developmental change when the measures themselves change with development? Most developmental studies of word learning use either looking (infants) or pointing (preschoolers and older). With little empirical evidence of the relationship between the two measures, developmental change is difficult to assess. This paper analyzes…

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…

Previous studies have found correlations between parent input and child language outcomes, providing prima facie evidence for a causal relation. However, this could also reflect the effects of shared genes. The present study removed this genetic confound by measuring English vocabulary growth in 29 preschool-aged children (21 girls) aged…

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…

Children acquire language embedded within the rich social context of interaction. This paper reports on a longitudinal study investigating the developmental relationship between conversational turn-taking and vocabulary growth in English-acquiring children (N = 122) followed between 9 and 24 months. Daylong audio recordings obtained every 3 months…

This study examined how inferences about epistemic competence and generalized labeling errors influence children's selective word learning. Three- to 4-year-olds (N = 128) learned words from informants who asked questions about objects, mentioning either correct or incorrect labels. Such questions do not convey stark differences in informants'…

Most language use is displaced, referring to past, future, or hypothetical events, posing the challenge of how children learn what words refer to when the referent is not physically available. One possibility is that iconic cues that imagistically evoke properties of absent referents support learning when referents are displaced. In an…

Previous work indicates mutual exclusivity in word learning in monolingual, but not bilingual toddlers. We asked whether this difference indicates distinct conceptual biases, or instead reflects best-guess heuristic use in the absence of context. We altered word-learning contexts by manipulating whether a familiar- or unfamiliar-race speaker…

Many Western industrialized nations have high levels of ethnic diversity but to date there are very few studies which investigate prelinguistic and early language development in infants from ethnic minority backgrounds. This study tracked the development of infant communicative gestures from 10 to 12 months (n = 59) in three culturally distinct…

Preschool teachers' perceptions about relationships with students (teacher-child relationships [TCRs]) predict children's subsequent social competence (SC) and academic progress. Why this is so remains unclear. Do TCRs shape children's development, or do child attributes influence both TCRs and subsequent development? Relations between TCRs and…

This study investigates the impact of evidentiality on source monitoring and the impact of source monitoring on false belief understanding (FBU), while controlling for short-term memory, age, gender, and receptive vocabulary. One hundred (50 girls) monolingual 3- and 4-year-olds from Turkey and the UK participated in the study in 2019. In Turkish,…

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…

This study investigates the influence of semantic maturation on early lexical development by examining the impact of contextual diversity--known to influence semantic development--on word promotion from receptive to productive vocabularies (i.e., comprehension-expression gap). Study 1 compares the vocabularies of 3685 American-English-speaking…

When referring to objects, adults package words, sentences, and gestures in ways that shape children's learning. Here, to understand how continuity of reference shapes word learning, an adult taught new words to 4-year-old children (N = 120) using either clusters of references to the same object or no sequential references to each object. In three…