Mechanical Tuning of Hair Bundles
Through a chain of mechanical processes, sound stimuli cause the deflection
of hair bundles of hair cells in the inner ear.
This mechanical process, which forms the basis of our sense of hearing, is
We have measured the motions of hair bundles in response to sound in an
isolated preparation of the cochlea of the alligator lizard Elgaria
This image shows cochlear motion at two planes of focus in response to a 4
kHz sound stimulus.
The hair cells near the top of the image respond best to tones with
frequencies near 4 kHz; those near the bottom respond best to frequencies
from 1 to 2 kHz.
Our measurements showed that the motion of these hair bundles depends on
both the sound frequency and the height of the hair bundle.