Function of the medial olivocochlear system in children with phonological disorders

PURPOSE: To verify whether children with phonological disorders present alterations in the medial olivocochlear system. METHODS: This is a prospective cross-sectional study in which 19 normal hearing children of both genders, with ages between 4 and 7 years, were divided into two groups: 11 children without phonological disorders (control group) and eight with phonological disorders (study group). The auditory condition was verified by visual examination of the external ear canal, pure tone audiometry, and tympanometry. The study included only children with hearing thresholds below or equal to 15 dB, type A tympanometry, and presence of acoustic reflexes. To evaluate the function of the medial olivocochlear system, it was carried out the evaluation of transient evoked otoacoustic emissions (TEOAE) with and without contralateral white noise at 60 dBHL. Data were statistically analyzed. RESULTS: The occurrence and average values of TEOAE suppression in right and left ears did not present differences in the frequencies of 1, 2, 3 and 4 kHz within groups. In the comparison of the mean and the occurrence of the suppressive effect of TEOAE between control and study groups, there was also no difference in the frequencies analyzed. CONCLUSION: Children with phonological disorders do not present alterations in the medial olivocochlear system, as evidenced by the occurrence of the suppressive effect of transient evoked otoacoustic emissions.

Otoacoustic emissions, spontaneous; Speech disorders; Auditory perception; Efferent pathways; Olivary nucleus; Child

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