Spoken Word Recognition Development in Children with Cochlear Implants: Effects of Residual Hearing and Hearing Aid use in the Opposite Ear

With broadening candidacy criteria for cochlear implantation, a greater number of pediatric candidates have usable residual hearing in their nonimplanted ears. This population potentially stands to benefit from continued use of conventional amplification in their nonimplanted ears. The purposes of this investigation were to examine the speech and language development of pediatric cochlear implant recipients with either profound or severe hearing loss in their nonimplanted ears, including a subset with severe hearing loss who continued wearing hearing aids in their nonimplanted ears; to evaluate whether children benefit from binaural use of cochlear implants and hearing aids; and to investigate the time course of adaptation to combined use of the devices together. Children were tested on a battery of speech recognition measures in quiet and background noise and language measures in quiet. The results suggest that, although children with different degrees of residual hearing have improved speech recognition and language skills after cochlear implantation, the developmental time course differs for the two groups. Children with severe hearing loss required more than 1 year of cochlear implant experience to demonstrate spoken word recognition gains, whereas children with profound hearing loss showed more benefit during the first year after cochlear implantation. For measures in which group performance differed, children with severe hearing loss had better speech recognition and language skills than the children with profound hearing loss. Furthermore, children with severe hearing loss who continued using hearing aids in their nonimplanted ears benefited from combining the acoustic input received from a hearing aid with the input received from a cochlear implant, particularly in background noise. However, this benefit emerged with experience. Our findings suggest that it is appropriate to encourage pediatric cochlear implant recipients with severe hearing loss to continue wearing an appropriately fitted hearing aid in the nonimplanted ear to maximally benefit from bilateral stimulation. They also suggest that speech and language gains for children with nonimplanted-ear residual hearing occur after children have at least one year of cochlear implant listening experience.