Emergence of speech sounds between 7 and 24 months of cochlear implant use

Abstract

Objectives

To investigate the process of speech development in five 42-month-old children with profound deafness who received cochlear implants (CIs) between 19 and 36 months of age and five normal hearing (NH) age mates.

Methods

Conversational samples were collected and transcribed. Sounds produced correctly within meaningful words (target sounds) and recognizable sounds produced in spontaneous productions (target-less sounds) were analyzed for all 10 children.

Results

Revealed that there was overlap in the total number of vowels and consonants produced by the two groups. The differences between the two groups were more evident in the target condition, whereas the two groups were more similar in the target-less condition.

Discussion

The similarities documented in the target-less repertoire of CI and NH children underscore the importance of examining the emerging sound system to predict the end-point sound system in children with CIs. Using target and target-less speech sound comparisons offers a supplementary view of the emergent process of speech sound development and is a valid method of analysis. Results suggest that early implantation may help some children with profound deafness develop speech sounds in a manner similar to NH age mates.

Keywords:

• Speech production
• Cochlear implant
• Target
• Target-less
• Phonetic repertoire

Acknowledgements

The authors gratefully acknowledge Ann Geers and Nancy Tye-Murray for their contributions during the development and data analysis stage of this work. We would like to acknowledge the work of Kari Delzer, graduate student at Central Institute for the Deaf, for her assistance with phonetic transcription and data input to CASALA.

Funding

This work was funded in part by NIH-NIDCD grants #DC01259 (Author3), #DC04168 (Author3), and the Oberkotter Foundation.