The influence of lexical knowledge on phoneme discrimination in deaf children with cochlear implants

Abstract

This paper addresses the questions of whether lexical information influences phoneme discrimination in children with cochlear implants (CI) and whether this influence is similar to what occurs in normal-hearing (NH) children. Previous research with CI children evidenced poor accuracy in phonemic perception, which might have an incidence on the use of lexical information in phoneme discrimination. A discrimination task with French vowels and consonants in minimal pairs of words (e.g., mouche/bouche) or pseudowords (e.g., moute/boute) was used to search for possible differences in the use of lexical knowledge between CI children and NH children matched for listening age. Minimal pairs differed in a single consonant or vowel feature (e.g., nasality, vocalic aperture, voicing) to unveil possible interactions between phonological/acoustic and lexical processing. The results showed that both the word and pseudoword discrimination of CI children are inferior to those of NH children, with the magnitude of the deficit depending on the feature. However, word discrimination was better than pseudoword discrimination, and this lexicality effect was equivalent for both CI and NH children. Further, this lexicality effect did not depend on the feature in either group. Our results support the idea that hearing deprivation period may not have consequence on lexical processes implied on speech perception.