Auditory, speech and language development in young children with cochlear implants compared with children with normal hearing

Objective: This study had two aims: (1) to document the auditory and lexical development of children who are deaf and received the first cochlear implant (CI) by the age of 16 months and the second CI by the age of 31 months and (2) to compare these children's results with those of children with normal hearing (NH). Methods: This longitudinal study included five children with NH and five with sensorineural deafness. All children of the second group were observed for 36 months after the first fitting of the device (cochlear implant). The auditory development of the CI group was documented every 3 months up to the age of two years in hearing age and chronological age and for the NH group in chronological age. The language development of each NH child was assessed at 12, 18,24 and 36 months of chronological age. Children with CIs were examined at the same age intervals at chronological and hearing age. Results: In both groups, children showed individual patterns of auditory and language development. The children with CIs developed differently in the amount of receptive and expressive vocabulary compared with the NH control group. Three children in the CI group needed almost 6 months to make gains in speech development that were consistent with what would be expected for their chronological age. Overall, the receptive and expressive development in all children of the implanted group increased with their hearing age. Conclusion: These results indicate that early identification and early implantation is advisable to give children with sensorineural hearing loss a realistic chance to develop satisfactory expressive and receptive vocabulary and also to develop stable phonological, morphological and syntactical skills for school life. On the basis of these longitudinal data, we will be able to develop new diagnostic tools that enable clinicians to assess child's progress in hearing and speech development. (C) 2010 Elsevier Ireland Ltd. All rights reserved.