Phonotactic Constraints on Infant Word Learning

Abstract

How do infants use their knowledge of native language sound patterns when learning words? There is ample evidence of infants' precocious acquisition of native language sound structure during the first years of life, but much less evidence concerning how they apply this knowledge to the task of associating sounds with meanings in word learning. To address this question, 18-month-olds were presented with two phonotactically legal object labels (containing sound sequences that occur frequently in English) or two phonotactically illegal object labels (containing sound sequences that never occur in English), paired with novel objects. Infants were then tested using a looking-while-listening measure. The results revealed that infants looked at the correct objects after hearing the legal labels, but not the illegal labels. Furthermore, vocabulary size was related to performance. Infants with larger receptive vocabularies displayed greater differences between learning of legal and illegal labels than infants with smaller vocabularies. These findings provide evidence that infants' knowledge of native language sound patterns influences their word learning.Keywords language acquisition; speech perception; word learning At its foundation, word learning requires mapping between sounds and meanings. To acquire a new lexical item, learners must associate a sound sequence representation with a meaning representation. Studies conducted over the past four decades have revealed that young infants possess remarkable speech perception skills, and become attuned to the sound structure of their native language very early in life (for a review, see Saffran, Werker, & Werner, 2006). A separate body of work investigating children's learning of word meaning has demonstrated that children possess a wide range of strategies and biases that allow them to access the appropriate meanings of new words (for a review, see Waxman & Lidz, 2006). However, the relationship between these two key aspects of language acquisition has only recently received attention (e.g., Fennell, Byers-Heinlein, & Werker, 2007;Mani & Plunkett, 2008;Stager & Werker, 1997; see also Saffran & Graf Estes, 2006 for a review).Before infants produce their first words, they gather a great deal of information about the sound system of the ambient language. At 6 to 8 months of age, infants discriminate many native and non-native language phoneme distinctions, but by 12 months, infants' discrimination is focused on contrasts that are relevant in their native language (e.g., Werker & Tees, 1984). Infants also learn about distributional patterns in the sound combinations of their native language. By 9 months of age, infants discriminate sound sequences that occur in their native language from sequences that do not occur; they prefer to listen to phoneme combinations present in the language Jusczyk, Friederici, Wessels, Svenkerud, & Jusczyk, 1993). Nine-month-olds also distinguish between words containing frequently occurring native language sound sequences from words contai...

Language facilitates event memory in early childhood: Child comprehension, adult-provided linguistic support and delayed recall at 16 months

“…We suggest that children with better general comprehension skills may be those children who are also better at creating and maintaining language-event associations. In support of this prediction, previous research indicates that receptive vocabulary is associated with novel word learning at 18 months, such that children with higher MCDI comprehension scores were able to discriminate between plausible and implausible object labels in a word learning task, whereas children with lower comprehension scores were not (Graf Estes et al, 2011). As we reported previously (Phung et al, 2014), we do not believe that the group differences in elicited imitation performance before the provision of the specific verbal prompt at the second session are associated with general measures of intelligence or cognitive competency, although language comprehension has been associated with later IQ (Bornstein & Hayes, 1998;Rose, Feldman, Wallace, & Cohen, 1991).…”

The sensitivity of children with SLI to phonotactic probabilities during lexical access

“…For example, 9-month-olds listen longer to target words when they were previously presented in a sentence context that provided good phonotactic cues (i.e., with low transitional probability at the boundary before and after the target word) than if they had heard them in a context that did not provide such cues (Mattys & Jusczyk, 2001). In a learning task, 18-month-olds look longer at objects that contain phonotactically legal than illegal labels (Graf Estes, Edwards, & Saffran, 2011). They also learn more common sound sequences faster (Graf Estes & Bowen, 2013;Schwartz & Leonard, 1982;Storkel, 2001;Storkel & Rogers, 2000) and earlier in development (GonzalezGomez, Poltrock, & Nazzi, 2013) than rare sound sequences.…”

The redundancy of phonemes in sentential context

“…Much like letters, phonemes in English occur with varying probability. Second-order redundancy in speech is conveyed by phonotactic probabilities, which play an important role in language acquisition [9][10][11][12] and processing. 13,14 Quantifying the degree to which listeners use this information, and how that compares to estimates from written language, has never been demonstrated to our knowledge.…”