Additive effects of phonetic distinctions in word learning

Abstract

While infants have been demonstrated to be sensitive to a wide variety of phonetic contrasts when tested in speech discrimination tasks [Eimas et al. (1971) et seq.], recent work [Stager and Werker (1997)] has shown that following habituation to a word–object pairing, infants of 14 months fail to notice when the place of articulation of the initial consonant is switched [b/d]. Using the same procedure, the present study has found that infants do not respond to a change in voicing [b/p]. They do, however, notice a switch between dissimilar words [lɪf/nim]. One interpretation of these findings is that 14-month-olds do not encode either place or voice distinctions in lexical representations, so that words differing in only these features are treated as identical. To test this hypothesis, the effect of combining featural contrasts is currently being investigated by examining whether infants do respond to a change in both place and voice [d/p]. If there is such an additive effect, the contrasts must be represented. This would entail that an explanation for the failure to distinguish words differing in only a single feature should invoke processing factors, rather than representational ones.

Infants' Ability to Learn Phonetically Similar Words: Effects of Age and Vocabulary Size

“…In summary, across a series of three studies we have found that, although infants of 14 months have difficulty learning phonetically similar words, by 17 and 20 months of age infants can learn phonetically similar words with only minimal exposure and with no contextual support. The finding with infants at 14 months of age replicates that reported by Stager and Werker (1997;Pater et al, 1998Pater et al, ,2001, and rules out the possibility that the lack of success at 14 months was due to simple procedural factors such as the amount of exposure during the familiarization phase or the physical similarity of the two objects to which infants were to associate the word forms. With a significantly increased trial duration and a stricter habituation criterion, and with the use of new objects that are visually much more distinct than those used by Stager and Werker, infants of 14 months still failed to learn to pair minimally distinct words with the two different objects, whereas infants of both 17 and 20 months of age succeeded.…”

“…How do these results map onto general theories of the relation between perceptual skills and word-learning abilities? We raised two possible explanations earlier for why the infants 14 months of age in Stager and Werker (1997;Pater et al, 1998Pater et al, , 2001; see also Hall6 & de Boysson-Bardies, 1996, with infants at 11 to 12 months) had failed to learn minimally different words whereas older infants, tested primarily in lexical access tasks, had succeeded at distinguishing known words from minimal-pair mispronunciations (Fernald et al, in press;Swingley & A s h , 2000;Swingley et al, 1999). One possible reason is that the difference in results stems from development: There is something different about older infants in comparison to younger infants that makes it possible for the older infants to learn and distinguish minimally different words.…”

Updates on becoming a native listener

“…In all cases, they show a movement toward privileged processing of just that information in speech which is necessary for properly segmenting words from the speech stream, and preparing the child to attach meaning to the class of words (content words) that are first acquired, A critical question we are have been addressing for the past few years is whether or not infants immediately use all of these language-specific sensitivities when they first begin associating words with their referents. Our results to date show that infants fail to distinguish minimally different words when the words are associated with objects although they easily distinguish these same forms when they are not linked to meaning (7,8). We interpret this pattern of results as suggesting a second "functional reorganization" when children first begin to learn words.…”

The first steps in word learning are easier when the shoes fit: comparing monolingual and bilingual infants

“…Despite the early emergence of language‐specific perception, infants do not initially make full use of their native language phonetic perception skills when they begin to learn words (Stager & Werker, 1997; Werker & Stager, 2000; Werker, Fennell, Corcoran & Stager, 2002; Pater, Stager & Werker, 1998, 2004). For example, Stager and Werker (1997) found that 14‐month‐old English‐learning infants were unable to learn the association between a novel word and a novel object when the labels for the objects were phonetically similar, / bIh / and /dIh/.…”