Effects of Early-Onset Deafness in the Developing Auditory System

Estimates of the incidence of congenital hearing loss in the United States range from one to six in every 1000 births. When undetected, early hearing loss results in significant developmental delay in language acquisition and substantial lifetime costs to society. Cochlear implants (CIs) have radically changed the rehabilitation of individuals with severe to profound sensorineural hearing loss. However, there is great variability in outcomes with the CI, at least some of which is due to the condition of the auditory nerve and cochlear spiral ganglion (SG) neurons that are the targets of CI stimulation. This has focused attention on maintaining better SG survival after deafness, an issue that is particularly important for pediatric CIs owing to the profound effects of early-onset hearing loss and expected long duration of CI use.