The Underwater Piano: Revival of the Resonance Theory of Hearing

Abstract

In 1857 Helmholtz proposed that the ear contained an array of sympathetic resonators, like piano strings, which served to give the ear its fine frequency discrimination. Since the discovery that most healthy human ears emit faint, pure tones (spontaneous otoacoustic emissions), it has been possible to view these narrowband signals as the continuous ringing of the resonant elements. But what are the elements? We note that motile outer hair cells lie in a precise crystal-like array with their sensitive stereocilia in contact with the gelatinous tectorial membrane. This paper therefore proposes that ripples on the surface of the tectorial membrane propagate to and fro between neighbouring cells. The resulting array of active resonators accounts for spontaneous emissions, the shape of the ear’s tuning curve, cochlear echoes, and could relate strongly to music. By identifying the resonating elements that eluded Helmholtz, this hypothesis revives the resonance theory of hearing, displaced this century by the traveling wave picture, and locates the regenerative receiver invoked by Gold in 1948.

Available Versions of this Item

• The Underwater Piano: Revival of the Resonance Theory of Hearing. (deposited 24 May 2000) [Currently Displayed]
  • Helmholtz's Piano Strings: Reverberation of Ripples on the Tectorial Membrane. (deposited 16 Aug 2001)