Development of Grammatical Accuracy in English-Speaking Children With Cochlear Implants: A Longitudinal Study

Purpose: We sought to evaluate the development of grammatical accuracy in English-speaking children with cochlear implants (CIs) over a 3-year span. Method: Ten children who received CIs before age 30 months participated in this study at 3, 4, and 5 years postimplantation. For the purpose of comparison, 10 children each at ages 3, 4, and 5 years with typical hearing were included as well. All children participated in a story-retell task. We computed percent grammatical communication units (PGCU) in the task. Results: Children with CIs showed significant improvement in PGCU over the 3-year span. However, they produced lower PGCU than children with typical hearing who had matched hearing age at 4 and 5 years postimplantation. At the individual level, some children with CIs were able to produce PGCU comparable to children with typical hearing as early as 3 years after implantation. Better speech-perception skills at earlier time points were associated with higher PGCU at later time points. Moreover, children with and without CIs showed similar rankings in the types of grammatical errors. Conclusion: Despite having auditory-perceptual and information-processing constraints, children who received CIs before age 30 months were able to produce grammatical sentences, albeit with a delayed pattern.