Changes in 2f1-f2 distortion product otoacoustic emissions following alterations of cochlear metabolism

This paper summarizes the results obtained from investigations in which distortion product otoacoustic emissions (DPOAEs) were studied together with other cochlear physiological parameters. The cochlear metabolism was subjected to three different experimental conditions: guinea pigs were either submitted to hypoxia, to an intra-cochlear perfusion of ouabain or to an intra-cochlear perfusion of naloxone. The data show that DPOAEs remain affected for a certain time after the metabolic perturbations were removed. The comparison of the behaviour of DPOAEs and of other cochlear parameters gives good indications on the way these different experimental procedures affect the functioning of the cochlea during and after their application.