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Updated: Apr 1, 2026

Physiological Preparation of Hair Cells from the Sacculus of the American Bullfrog Rana catesbeiana
Published on: March 17, 2017
Acoustic analysis of the frequency-dependent coupling between the frog's ears
1Department of Speech and Hearing Sciences, Indiana University, 200 South Jordan Avenue, Bloomington, Indiana 47405, USA.
Abstract:
The ears of anurans are coupled through the Eustachian tubes and mouth cavity. The degree of coupling varies with frequency showing a bandpass characteristic, but the characteristics differ between empirically measured data based on auditory nerve responses and tympanic membrane vibration. In the present study, the coupling was modeled acoustically as a tube connected with a side branch. This tube corresponds to the Eustachian tubes, whereas the side branch corresponds to the mouth cavity and nares. The analysis accounts for the frequency dependency shown by the empirical data and reconciles the differences observed between the coupling as measured by tympanic membrane vibration and auditory nerve responses.
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