Maturational delays in cortical evoked potentials in cochlear implant users.

We studied the effects of prolonged auditory deprivation in children in whom auditory stimulation was restored by a cochlear implant. The latency of the P1 component of the late cortical potential was used as the indicator of auditory system maturation. For normal-hearing children there is a gradual evolution of evoked potential features that extends through adolescence with P1 latency becoming adult-like at about age 15. It appears that maturation of P1 latency in normal and implanted children occurs at the same rate, but the time to maturity in implanted subjects is delayed by an amount approximately equal to the duration of deafness.