Contralateral suppression of transient evoked otoacoustic emissions in children with phonological disorder.

BACKGROUND:Perception of acoustic details in the speech signal is important for speech sound development. The medial olivocochlear pathway, a part of the auditory efferent system, plays a role in stimulus-related control of the cochlea. One clinical tool to evaluate the medial olivocochlear activity, which is thought to improve speech perception in noise, is the suppression of otoacoustic emissions. AIMS:This study investigated the suppression of transient evoked otoacoustic emissions in children with phonological disorder in comparison with that in typically developing controls. STUDY DESIGN:Case-control study. METHODS:A total of 23 children with phonological disorder (aged 5-10 years) and 21 age- and sex-matched controls (P > 0.05) participated in the study. Participants had pure-tone thresholds ≤ 15 dB hearing loss and normal middle ear functions. Transient evoked otoacoustic emissions with and without contralateral acoustic stimulation were measured. RESULTS:Although the mean transient evoked otoacoustic emissions suppressions were lower in the group with phonological disorder than in the controls, these differences were not statistically significant (P > 0.05). No left/right ear asymmetry of transient evoked otoacoustic emissions suppression was detected in either of the groups (P > 0.05). CONCLUSION:Children with phonological disorder did not show alterations in medial olivocochlear functioning in the medial olivocochlear activity as measured by the contralateral suppression of transient evoked otoacoustic emissions.