Early Theories of Hearing

Abstract

The intellectual heritage of Greek natural philosophy includes a number of speculations and hypotheses dealing with the perception of sound. Through the middle ages all theories of hearing were characterized by the central role of the “aer internus.” As anatomical data became available concerning the structures in the middle and inner ear, and as the physics of sound became better understood, the need for theories in reasonable agreement with experimental facts arose. In 1683, the collaboration of the anatomist Duverney and the physicist Mariotte yielded the first “resonance theory” of hearing. Duverney identified the bony fibers of the cochlear partition as the tuned elements. This localized the high frequencies at the apex and the low frequencies near the stapes. But Duverney and his contemporaries continued to cling to the belief that air was present inside the cochlea. It was not until 1760 that Cotugno established definitely the presence of fluid throughout the labyrinthine cavity. During the 18th century there was much verbal disagreement among the various physiologists concerning the “resonators” in the ear and concerning the localization of high and low frequencies. In 1822, Magendie dismissed the whole resonance hypothesis with a single sentence since, as he said, “no one believes it at the present day.” When Helmholtz developed his theory in the second half of the 19th century the situation had changed: he had new building stones at his disposal, among which microanatomical data collected by Corti and Hensen, Fourier's theorem and Ohm's acoustic law were the most important.