Habituação do reflexo cócleo-palpebral no período neonatal e desenvolvimento do processamento auditivo

Abstract

The absence of habituation to repeated sound stimuli in neonates can predict alterations in the auditory processing. It was objectified to verify the existence of an association between the presence/absence of the blink reflex habituation in the neonatal period and auditory processing. The occurrence of blink reflex habituation was studied in 33 neurologically normal neonates, who had their behavioral responses analyzed and classified according to Azevedo (1993), between nine and 25 months of age. Habituation of the blink reflex was verified using a sound stimulus of nearly 90 decibels (dB). The stage of the auditory processing development was evaluated through a sound stimulus of nearly 41 dB. Statistical data analyses were made with Fischer and Chi-square tests. Of the 33 studied children, 22 presented blink reflex habituation in the first stage of the study. In seven of them, the auditory processing stage matched their chronological age, while in 15 of them, the auditory processing stage was found inadequate to their chronological age. Eleven children failed to present habituation of the blink reflex in the first stage of the study. From this group, eight children disclosed auditory responses that were adequate to their chronological age, and three, inadequate. A statistically significant association between the presence of blink reflex habituation and an auditory processing delay was verified as well as between the absence of the blink reflex habituation and chronologically suitable responses. The presence of blink reflex habituation in the neonatal period does not seem to be a predictive factor of the adequate auditory processing.