Language evolution in children with cochlear implants.

Abstract

The capacity to incorporate significant words into the existing vocabulary and to use these words to form sentences with more mature syntactic structures emerges over a considerable time course in young deaf children who have undergone a cochlear implantation. The purpose of this follow-up study is to document the nature and time span of language production--in morphosyntactic and lexical skills--when a child's first experience with language sounds is provided artificially through electrical stimulation. To examine the development of these two aspects of linguistic processing, five deaf French children, all enrolled in similar postimplantation educational settings, were individually assessed at 6-month intervals over a period of 18 months. Computerized analyses were derived from their spontaneous speech in a 20-min standardized play session. Results for mean length of utterance and vocabulary revealed gradually improving performance for most children, in spite of the generally low starting point. Both measures of production nevertheless remained well below the norms established for normally hearing children. Although the achievement of higher production scores, which underlies more effective interpersonal exchanges, is evident after only 1 year of device use, it is clear that improvement does not always occur at the same pace, as shown by two of the children. This emphasizes the importance of longitudinal studies in documenting intersubject variability and intrasubject stability throughout the experience with an implant.