Cortical auditory evoked potentials in full-term and preterm neonates

Purpose: To measure the exogenous components of the cortical auditory evoked potential (CAEP) in term and preterm newborns and compare them considering the variables latency and amplitude. Methods: This is a cross-sectional, prospective, comparative, contemporary study. One hundred twenty-seven newborns were evaluated; 96 of these were included in the study after analysis of the exams by three referees. Participants were divided into two groups: Term Group: 66 infants and Preterm Group: 30 neonates. The recordings of CAEP were performed using surface electrodes with newborns comfortably positioned in the lap of their mothers and/or guardians in natural sleep. To this end, binaural verbal stimuli were presented with /ba/ as the frequent stimulation and /ga/ the rare stimulus, at an intensity of 70 dB HL, through insert earphones. The presence or absence of exogenous components and the latency and amplitude of P1 and N1 were analyzed in both groups. Pertinent tests were used in the statistical analysis of data. Results: The latency of the waves P1 and N1 was smaller in participants in the Term Group. However, there were no statistically significant differences in the amplitude of P1 and N1 between the groups. No difference between the groups was found when comparing the presence and absence of the components P2 and N2. Conclusion: It is possible to measure the CAEP in term and preterm neonates. There was influence of the maturational process only on the measure of latency of the components P1, binaurally, and N1, in the left ear, which were smaller in participants in the Term Group.