Effects of Salicylates on Evoked Otoacoustic Emissions and Remote Masking in Humans

Abstract

The aim of this study was to evaluate, in young volunteer subjects, the effects of salicylates on evoked otoacoustic emissions (EOAEs), which presumably reflect an active mechanical process in the cochlea due to outer hair cell (OHC) activity, and on remote masking (RM), which has been proposed as a useful tool in the study of the non-linear cochlear distortion products generated by high-frequency maskers. Data from the present research are consistent with the literature showing a reversible effect of salicylate leading to elevated hearing thresholds and reduced EOAE amplitudes. From the point of view of new findings, the results demonstrate a reversible effect of salicylates on RM magnitude, which decreases as serum salicylate concentration increases. As described previously by other authors, salicylate selectivity inhibits OHC motility and, in consequence, reduces the amplitude of the motion of the basilar membrane. According to these data it is very likely that the observed reduction in RM magnitude after salicylate administration is also the result of the decreased ability of the OHCs to contract and of the reduced basilar membrane motion. The results are consistent with the conclusion that the OHC system function plays a role in producing RM.

Key Words:

• Evoked otoacoustic emissions
• Remote masking
• Ototoxicity
• Salicylate