Wave Motion in the Cochlea Caused by Bone Conduction

Psychophysical and physiological experiments have shown that a tone transmitted to the cochlea by bone conduction can be compensated by an airborne sound. From these experiments it has been deduced that the vibration pattern of the cochlear partition does not depend upon the path by which sound is transmitted to the cochlea. This hypothesis has been confirmed by direct observation of the vibration pattern in cochlea models and by measurements of cochlear microphonics. From both kinds of experiments attempts have been made to draw conclusions concerning the theory of cochlear dynamics.In an effort to explain the fact that the vibration pattern of the cochlear partition is independent of the path by which the sound is transmitted to the cochlea, a mathematical analysis has been performed. First, by means of the hydrodynamic principle of continuity, it has been demonstrated that the vibration of the cochlear partition caused by a tone introduced into the cochlea either through the bony wall or through an art...