On the effect of certain drugs,notably quinine,on the acuity of hearing

The purpose of this investigation was to determine the degree of deafness following the administration of quinine and also to ascertain, if possible, whether or not the tinnitus which accompanies this intoxication has any appreciable effect on the acuity of hearing at any and all pitches. While these experiments were under way the writers found that Macht, Greenberg and Isaacs had published a similar investigation in reference to antipyretics. It was thought desirable, for reasons which will appear later, to check on the results obtained by these writers. The quantitative tests submitted in this paper were all made by Kranz 1 with a thermophone provided with a new frequency variator of his own design. The drug effects were studied both subjectively and objectively by Pohlman 2 We are indebted to Colonel George Fabyan of Riverbank, Geneva, Ill., for the opportunity of collaborating on this problem of applied physics.

The article by Macht, Greenberg and Isaacs 3 reviews the literature thoroughly and includes certain notations on the effects of quinine of which we shall speak later. They confined their attention to antipyretics and to certain combinations of these drugs. In a general way, they exhibited small doses of the various drugs to normal individuals and after an hour interval tested the acuity of hearing. This was done by comparing the distance at which a watch tick could be heard before and one hour after the administration of the drug. The difference therefore gave a reading of greater or lesser distance. The authors state that the figures are after all only empirical guides because they recognize “true intensity varies as the square of the distance of the sounding object.”

Inasmuch as this paper is mainly directed toward suggesting More definite methods, it may be well to point out certain disadvantages in the use of the watch as a test for minimum audibility.