Nasality patterns in word productions of children with cochlear implants: Evidence from Greek

Abstract

Typical speech production development requires adequate auditory input. Children who are born deaf or become deaf in early childhood display atypical speech patterns, especially for articulatory actions that cannot be seen. Such actions include tongue backing, laryngeal actions, and velar function. Several previous authors have discussed how inadequate auditory input affects anterior-posterior tongue positioning and laryngeal parameters, compromising phonetic contrasts (e.g., vowel and voicing distinctions), but few studies have directly assessed velar control in hearing-impaired children. This work presents nasometer data for Greek-learning children with cochlear implants [CI] and age- and sex-matched normal hearing [NH] controls, ages 5-16 years. Participants produced single words, elicited in response to visual and auditory prompts. Bisyllabic word types of varying stress pattern were contrasted in nasality and position of the target consonant. Based on the two nasometer microphone signals (oral and nasal), word and segment boundaries were defined, and nasometer values over these intervals were extracted. We will present whole-word data, comparing nasalance values between NH and CI children, and examples showing atypical oral-nasal timing in the CI population. This preliminary analysis shows some of the ways in which hearing-impaired children with cochlear implants may show unusual patterns of velar control.