While it should come as no huge surprise, recent work by Johanna Grant Nicholas, Ph.D., from Washington University School of Medicine in St. Louis and colleague Ann E. Geers, Ph.D., from the Southwestern Medical School at the University of Texas at Dallas, shows that the younger a deaf child receives a cochlear implant, the better their speech skills will be at age 3.5…
“Ninety percent of children born deaf are born to hearing parents, and these parents know very little about deafness,” Nicholas says. “They don’t know how to have a conversation in sign language or teach it to their children. Many of these parents would like their children to learn spoken language.”
The researchers tested the spoken language skills of 76 children, all 3 and a half years old, who had cochlear implants and compared those results to the length of time each child had his or her implant. They found that with increased implant time, children’s vocabulary was richer, their sentences longer and more complex and their use of irregular words more frequent. The researchers’ work was reported in the June issue of Ear and Hearing.
Nicholas notes that many of the children who received cochlear implants at the youngest ages have nearly the same spoken language skills as children with normal hearing. The researchers’ further studies — not yet published — suggest that by age 4 and a half, children who had cochlear implants very early often have normal speech and can potentially enter kindergarten with their hearing peers.
“Kids with residual hearing can get some help from hearing aids, but cochlear implants give a tremendous hearing advantage over hearing aids — the implants provide more sound information,” Nicholas says. “For example, high-frequency sounds are magnified more with cochlear implants, so kids can hear ‘s’ sounds and ‘ed’ endings better. So they tend to catch on to plurals and verb tenses faster.”
While studies like this and others favor early implantation, the decision for or against cochlear implantation is frequently put off, Nicholas indicates. Hearing parents often find they need time to learn about deafness and potential treatments. Implantation also may be delayed to make certain an infant’s deafness has not been misdiagnosed.
Even when deafness is confirmed, the idea of head surgery for their baby makes many parents hesitate. And they may be daunted by the fact that a cochlear implant is forever — the device destroys any residual hearing so that hearing aids are no longer an option.
When cochlear implants first entered the scene, most of the recipients were adults who had gone deaf later in life, frequently having never learned sign language, and as such had a huge incentive to regain functional hearing immediately. However, when it comes to younger children for whom there might someday be a biological solution to deafness, the decision can be tougher for parents to proceed to a currently acceptable solution. Hopefully this work will provide an important data set upon which to base a decision.
More from the press release or from the article in Ear and Hearing…