Development of auditory evoked potentials.

The development and maturation of the human auditory system appears to occur in parallel at all levels from middle ear to cortex. The maturation of evoked potentials from auditory brainstem to auditory cortex can be described by equal percentage changes in equal time periods. This is essentially the exponential growth model with equal maturation rate for each station. The auditory nerve maturation occurs at a rate considerably faster than that for more central parts of the nervous system. Premature birth does not seem to affect the maturation rate and time to maturity of the auditory brainstem potentials, so that experience does not seem to affect physiological maturation. However, there is a clear difference in maturation rates for different frequency regions, suggesting that the time course of structural maturation has an effect. Behavioral changes in hearing threshold show maturation rates similar to the physiological ones for the central nervous system.