Cortical maturation of long latency auditory evoked potentials in hearing children: the complex P1-N1-P2-N2.

Purpose: The purpose of this study was to monitor the emergence and changes to the components of the Long Latency Auditory Evoked Potentials (LLAEP) in normal hearing children.

Methods: This longitudinal study included children of both genders: seven aged between 10 and 35 months, and eight children between 37 and 63 months. The electrophysiological hearing evaluation consisted of analysis of LLAEP obtained in a sound field generated with loudspeakers positioned at an azimuth of 90°, through which the syllable /ba/ was played at an intensity of 70 dB HL. Each child underwent an initial evaluation followed by two re-evaluations three and nine months later.

Results: The emergence of LLAEP components across the nine-month follow-up period was observed. P1 and N2 were the most common components in children of this age range. There was no statistically significant difference regarding the occurrence of P1, N1, P2, and N2 components amongst younger and older children. Regarding latency values, the greatest changes overtime were observed in the P1 component for younger children and in the N2 component for older children. Only the P1 component significantly differed between the groups, with the highest latency values observed in younger children.

Conclusion: LLAEP maturation occurs gradually and the emergence of complex components appears to be related more to the maturation of the central auditory nervous system than to chronological age.