Effect of Contralateral Noise on Acoustic Reflex Latency Measures.

OBJECTIVE The present study was conducted to determine the effect of contralateral broadband noise on acoustic reflex latency (ARL). MATERIALS AND METHODS Acoustic reflex latency changes for 10 and 90% on- and off-time acoustic reflexes with contralateral broadband noise were measured in 30 adults with normal hearing. RESULTS The results of the study demonstrate that there was a latency prolongation for reflex on-time (10 and 90%) and latency reduction for reflex off-time (10 and 90%). This effect was seen for 500, 1000, and 2000 Hz reflex-eliciting signals. The results also showed that there was no effect of gender on latency changes in acoustic reflexes. CONCLUSIONS Latency changes may explain efferent auditory system mechanisms used for the protection of the cochlea and improvement in speech perception. Thus, contralateral changes of ARL can serve as an additional tool to assess the efferent system functioning.