The majority of children with postlingual deafness have meningitis as the cause of deafness. The majority of children receiving implants are prelingually deaf and may be completely unfamiliar with sound. Trends in effective use of cochlear implants have been observed. The postimplant performance of children with acquired or congenital deafness before age three show speech perception results that are similar. The postimplant performance of children with postlingual deafness is better on most outcome measures, but those differences become smaller over time.
Performance is better for children who are implanted when younger than age four.
Intensive auditory training should include training in detection of sounds as well as recognition of closed sets of spoken works. More recent changes in candidacy criteria are leaning toward relaxing that criterion. The performance of children with some residual hearing has resulted in a recommendation to include them in the selection group. Further research detailing changes with respect to duration of implant use, significance of age of onset of deafness, and age of implantation is needed. Some adults can recognize sounds in an open set with hearing alone.