The influence of contralateral acoustic stimulation on click-evoked otoacoustic emissions in humans.

Contralateral acoustic stimulation has the effect of reducing the amplitude and shifting the phase of click-evoked OAEs. This effect is thought to be mediated via the medial efferent system and, therefore, the presence of this effect could be used to test the integrity of the neural pathway from one cochlea to the other. With a clinical application in mind, a technique for demonstrating the influence of contralateral acoustic stimulation on click-evoked OAEs was designed to overcome fluctuations in patient and environmental noise. The results of this test on three normal subjects and a patient with a posterior fossa lesion are described.