Changes in Spontaneous and Evoked Otoacoustic Emissions and Corresponding Psychoacoustic Threshold Microstructures Induced by Aspirin Consumption

Spontaneous otoacoustic emissions, delayed evoked emissions, synchronous evoked emissions and psychoacoustical threshold microstructure were monitored (in two subjects) before, during and after the consumption of 3.9g of aspirin per day for three consecutive days (12 doses of three 325mg tablets every 6 hours). Spontaneous emissions followed a pattern similar to that found by McFadden and Plattsmeir (1984). Evoked emissions were also reduced by aspirin consumption but persisted longer and recovered sooner. Reduction of psychoacoustic threshold microstructure associated with the emissions followed much the same time course as the evoked emissions. In most instances the reduction of threshold microstructure began with a lowering of threshold maxima (with threshold minima remaining relatively constant) and ended with all thresholds elevated.