Urdu-English Perceptual Confusions in Bilingual Children with Normal Hearing and Cochlear Implants: An Analysis of...

Background and Aims: Accuracy in speech perception in bilingual children is influenced by two phonological systems. This study compares phonological development in bilingual Urdu-English (UE) children with CIs with their hearing-age-matched peers with normal hearing (NH), by investigating whether bilingualism or any spectral limitations of CI impact perception of UE phonemes. Method and Procedures: Children (n = 57) aged 3; 0-6; 11 years (28 CI, 29 NH) were assessed for speech perception using a custom-designed UE Speech Perception Test (UE-SPT), in quiet and noise (+5 dB SNR). Responses were analysed using confusion matrices, across phonological parameters of place, manner, and voicing to determine error patterns. Outcomes and Results: Significant deficits in CI children were found across all features, with voicing discrimination showing the largest errors (effect sizes d > 6), exacerbated by noise, especially for Urdu aspirated stops. CIs mastered only 8.3% Urdu-aspirated consonants at 6; 11 years compared to 91.7% mastered by NH peers, indicating critical language-specific vulnerabilities. Backing and substitutions errors were particularly seen in CI's speech, whilst manner was preserved. Conclusion and Implications: UE bilingual phonological complexity compounded by inadequate speech processing abilities in CIs challenges them, underscoring urgent need for targeted speech therapy interventions focusing voicing contrasts and aspirated consonants, as well as environmental accommodations that reduce noise interference and enhance listening through CI, to optimise educational outcomes. This research contributes vital clinical guidance for supporting bilingual children with cochlear implants, addressing both environmental, technological and linguistic challenges.