Acoustic Analysis of Fricatives /s/ and /ʃ/ and Affricate /ʧ/ in Persian-Speaking Cochlear-Implanted Children and Normal-Hearing Peers

Abstract

Background and Aim: Hearing-impaired individuals have difficulty comprehending and producing speech sounds. Cochlear implantation is used to augment hearing. The present study aims to compare the production of fricatives /s/ and /ʃ/ and affricate /ʧ/ by Persian- speaking Cochlear-Implanted (CI) and Normal-Hearing (NH) children Methods: Fifteen Persian-speaking NH children and 15 Persian-speaking CI children, matched for age, gender, and general health conditions, were included in the study. The stimuli included two voiceless Persian fricatives /s/ and /ʃ/ and one voiceless Persian affricate   /ʧ/ along with the open front vowel /æ/ in three Consonant-Vowel (CV), Consonant-Vowel- Consonant (CVC), and Vowel-Consonant (VC) contexts (/sæ/, /æsæ/, /æs/, /ʃæ/, /æʃæ/, /æʃ/,/ʧæ/, /æʧæ/, /æʧ/). After recording all utterances, Praat software was used to measure the friction duration, rise time, and spectral peak of the consonants Results: The CI children could not distinguish between /ʃ/ and /ʧ/ and produced affricate /ʧ/ as an allophone of /ʃ/ (p=0.01). Moreover, distinguishing between two fricatives /s/  and /ʃ/ was difficult for both groups. While NH children slightly treated these two sounds differently, the CI group produced fricative /s/ as an allophone of /ʃ/ (p=0.02). The rise time of /ʃ/ was longer in the NH children, except for /ʧæ/, where the CI children had a longer rise time. Conclusion: The speech of CI children is different in producing /s/, /ʃ/, and /ʧ/ from their NH peers. The results can help speech therapists, clinical linguists, and application designers focus on speech sounds that are challenging for CI children to produce. Keywords: Cochlear implant; speech production; fricatives; affricate