[Quantitative characteristics of the basilar membrane in the mammalian cochlea]

The variations in width and height of the basilar membrane along the cochlea in four species of laboratory animals: white rat, guinea pig, chinchilla and cat have been investigated. The results obtained have been used to calculate the height/width ratio along the cochlea, suggested by Bruns as an estimate of basilar membrane stiffness. The given characteristic is practically identical in all species studied despite the differences in the frequency ranges of auditory reception and, therefore, cannot be used either for characterizing the basilar membrane stiffness or for frequency mapping the cochlea of mammals.