The error patterns of phonemes in children with prelingual hearing loss: A comparison between hearing aid and cochlear implant users

Objective To reveal differences in error pattern of phonemes and articulation between children using cochlear implants (CIs) and those using hearing aids (HAs) due to prelingual hearing disorder and help the education of children with prelingual hearing loss. Method Children with prelingual hearing loss who were receiving auditory-verbal preschool education at an auditory center for hearing-impaired children (Fujimidai Auditory Center, Tokyo, Japan) from 2010 to 2020 were analyzed retrospectively. All participants underwent pure tone audiometry and monosyllabic intelligibility tests. The error answers were categorized into five patterns which was characterized by the substitution, addition, omission, failure, and no response according to consonant errors. In addition, the consonant errors classified into the manner of articulation and the differences of error patterns were analyzed between the HA and the CI group descriptively. Results A total of 43 children with bilateral HAs and 46 children with bimodal CIs or bilateral CIs were enrolled. No significant between-group differences in median phoneme intelligibility were found. The most common error pattern was substitution in both HA and CI groups. The error number of addition pattern in the HA group was smaller than in the CI group. In both groups, the most common errors of articulation were flap errors, and the most common error patterns were flaps to nasals, nasals to nasals, plosives to plosives. In the HA group, plosives and nasals tended not to be recognized and in the CI group plosives were prone to be added to vowels. Conclusions There were some different error patterns of articulation and consonant substitution between groups. Clarifying differences of phoneme that are difficult to hear and tend to be misheard would help for creating an effective approach to auditory training for children with hearing loss.