Patterns of hair cell loss in chick basilar papilla after intense auditory stimulation. Frequency organization.

Ten-day-old chicks were continuously exposed to pure tones (500, 1 500, or 3 000 Hz) at 125 dB SPL for 12 hours and sacrificed 10 days after exposure. The basilar papillae were embedded in plastic, sectioned and hair cells were counted at 100-mum intervals throughout the length of the papilla. The position of hair cell loss along the basilar membrane varied systematically as a log-linear function with the frequency of stimulation. This systematic relationship was used to predict the frequency organization of the chick basilar papilla. It is concluded that although the avian basilar papilla differs greatly in morphological detail from the mammalian cochlea, its response to intense acoustic stimulation is quite similar.