Early cochlear implantation in children allows normal development of central auditory pathways.

The goal of this study was to determine whether there is a sensitive period during early development when a cochlear implantation can occur into a minimally degenerate and/or highly plastic central auditory system. Our measure of central auditory deprivation was latency of the P1 auditory evoked potential, whose generators include auditory thalamocortical areas. Auditory evoked potentials were recorded in 18 congenitally deaf children who were fitted with cochlear implants by 3.5 years of age. The P1 latencies of the children with implants were compared with the P1 latencies of their age-matched peers with normal hearing. There was no significant difference between the P1 latencies of the children with implants and the children with normal hearing. The present results suggest that early implantation occurs in a central auditory system that is minimally degenerate and/or highly plastic. Studies are ongoing to assess the consequences to the developing central auditory system of initiating electrical stimulation at later ages.