The effects of age at implantation on speech intelligibility in pediatric cochlear implant users: Clinical outcomes and sensitive periods

Abstract

This study assessed the effects of age at implantation on the speech intelligibility of congenitally, profoundly deaf pediatric cochlear implant users. The children received implants during the first eight years of life and were divided into subgroups based on their age at implantation. The children's tape recordings of standard sentences were digitized and played back to normal-hearing listeners who were unfamiliar with deaf speech. Intelligibility was measured as the number of words correctly identified averaged across all listeners. The data showed that earlier implantation had a positive and significant effect on the speech intelligibility of cochlear implant users. The results also suggested that a gradual decline in the ability to acquire spoken language skills may occur over time and, furthermore, cochlear implantation before the age of two years may yield significantly better speech intelligibility outcomes than later implantation.