Arrangement of Hair Cells
The hair cells of the organ of Corti are arranged in four rows along the length of the basilar membrane. Individual hair cells have multiple strands
called stereocilia. There
may be 16,000 - 20,000
such cells. The place theory
of pitch perception suggests
that pitch is determined by
the place along this collection at
which excitation occurs. The pitch
resolution of the ear suggests a
collection of hair cells like this
associated with each distinguishable pitch.
This is another conception of the arrangement of the outer three rows of hair cells, consistent with the above picture, but showing that a cluster of the cilia is associated with a single hair cell. It is drawn roughly from the work of McGutin. I think that the best that we know about the cilia arrangements comes from electron micrographs like those of Hudspeth.