Objective: To compare characteristics of vowe1 production in normal hearing typical Urdu-speaking children with hearing impaired children using Coch1ear Implants, focusing on time duration and first & second formant frequencies.

Methodo1ogy: This comparative cross-sectional study was conducted at Riphah International University from January to June 2023. Using nonprobability convenience sampling study recruited N=36 children (20 normally hearing & 16 hearing impaired children using cochlear implants with hearing ages of 2 to 5 years. A self-developed questionnaire was used for data collection. Participants were provided with specific sentences consisting of words made with short and 1ong vowels during their sessions. Three different words were made from each vowe1 for three different responses. PRAAT software and SPSS Version 25 were used for data collection.

Resu1ts: When comparing children with cochlear implants to those with normal hearing, there were notable differences in the formant 1 and formant 2 for short and long vowels at three specific points (R1, R2, R3). Additionally, significant variations were identified at R1 (p = 0.017), R2 (p = 0.024), and no significant variation at R3 (p = 0.066). The findings displayed noteworthy differences in F1 for /ʊ/ among children with atypical development compared to those with typical development. These variations were consistent across all three responses (R1, R2, R3). The mean duration for most of the long vowels like /ɔ/ , /o/ ,vowel revealed a significant difference between the two groups in R1, & the mean duration of /ae/ vowel was significantly different in all responses (p < 0.001).

Conc1usion: In Urdu-speaking children, discernible differences in formant frequencies 1 and 2, are present between normal-hearing children and those with cochlear implants. The varying sound patterns of the vocal tract illustrate the impact of cochlear implants on vowel pronunciation. These implants significantly influence the spectral aspects of speech, making it critical for a thorough assessment approach to consider both temporal and spectral factors in therapy.