Language discrimination in children with cochlear implant: Neural plasticity and age of implantation as critical variables

Discriminación del lenguaje en niños con implante coclear: Plasticidad neural y edad de implantación como variables críticas

Introduction: Cochlear implants in children were approved since the eighties. Investigations on the development of the auditory pathway suggest that early placement of a cochlear implant in children with prelingual deafness would provide greater benefits in language discrimination. This work seeks to establish the relationship between the age of implantation of children who have suffered prelingual hearing loss and language discrimination, both in a closed and open context, as well as describing how 50% of language discrimination is achieved in different groups in different contexts. open, considering this point as a functional threshold for the proper understanding of an oral message.
Methods: A retrospective descriptive study was conducted with patients implanted in the Santa Fé Foundation of Bogotá and the Hospital of San José, from 1992 to 2001, including 76 patients with prelingual hearing loss and a minimum follow-up of 36 months in tests for open and closed context.
Results: The patients were divided into four groups according to the age of implantation in years of age. Group I from 0 to 3 years, group II from 4 to 6 years, group III from 7 to 9 years and group IV from 10 to 12 years. The I and II presented better performance in language discrimination in the open context and the first to reach 50% was group I, performing it towards 20 months. In the closed context, no important differences were found.
Conclusion: The results indicate that early implanting a patient with prelingual hearing loss could offer the advantage of stimulating the auditory pathway in the gold stage, in which the phenomenon of neural plasticity and active maturation is still present. This study suggests that the ideal age of implantation is below three years.

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