Articulatory Characteristics as Functions of Articulation Distance and Articulatory Direction in Children with Cochlear Implants

Abstract

Objectives: Although children with cochlear implantation use correct pronunciation, many of them have difficulties with producing details of speech. The main aim of this study was to measure the articulation features of speech in well-performing children with cochlear implants (CIs).Methods: The participants were 15 children with CIs, with a mean age of 7 years (range: 5-10 years). A control group of children with typical hearing (TH) was included. Nonwords were manipulated in the form of different articulation distances and articulation movement directions. We measured phoneme accuracy, the ratio of vowel duration between the first and the second consonant, and the slope of the second formant transition (F2).Results: The two groups showed similar performance in the phoneme accuracy and the ratio of vowel duration, but the CI group produced sensitive changes according to the first consonant of nonwords and the articulation distance of the consonant pair. The CI group showed a higher slope of F2 than the TH group.Conclusion: These results suggest that children with CIs can control a range of motion and the speed of articulation organs, but their articulatory control abilities are less sophisticated and less stable. This study is meaningful in that it examined the articulation manipulation ability of children with cochlear implantation, which is perceptually difficult to distinguish, through an acoustic-phonetic evaluation method.