A frequency-position map for the chinchilla cochlea.

Frequencies of tones are mapped on to distances along the organ of Corti by associating behaviorally measured threshold shifts with regions of hair-cell loss. The central tendency found for 95 frequency-position matches by four observers on 21 ears is approximated by a straight-line, log-linear relation between frequency and position. Only a small portion of the considerable variation of individual matches around this function could be explained by length of the organ of Corti. Other unidentified factors appear to be responsible for most of these variations.