This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
How do infants learn words? Before they can attach meaning to words, children must understand what constitutes a word in their language. This task is complicated by the problem of variability: Everytime we hear a particular word, its physical form changes as a function of the speaker, their emotional state, and the words that surround it. None of these changes alter the meaning of a word, so listeners must disregard these changes when deriving word meanings. This is often termed "the variability problem." The variability problem has been extensively researched in adults but has received relatively little attention in the population on whom it is likely to exert the greatest influence - infants and young children who are building their first vocabulary. The work proposed probes the effects of variability on the genesis and expansion of early vocabularies in both monolingual and bilingual learners. The questions addressed use standard behavioral paradigms established in infant language processing research to investigate how infants reduce complex linguistic input to its meaningful essentials. Analyses focus on the efficiency and accuracy with which children learn words in spite of everyday variability and on the mechanisms that facilitate this process. Findings are expected to reveal possible mechanisms by which word learning emerges and matures in both young bilingual and monolingual learners.
The overall importance of this work lies in its focus on a fundamental, yet unresolved, question in language acquisition: How do children develop knowledge about words given the immense variability of human speech? The number of infants raised in multilingual homes from birth is increasing rapidly in the United States. This research will inform evidence-based practice (including child-rearing practices) and policy by exploring the consequences of bilingualism for early vocabulary development.
