Specializations for sharp tuning in the mustached bat: The tectorial membrane and spiral limbus

doi:10.1016/0378-5955(91)90161-2

Hearing Research

Volume 56, Issues 1–2, November 1991, Pages 122-132

https://doi.org/10.1016/0378-5955(91)90161-2 Get rights and content

Abstract

The sense of hearing in the mustached bat, Pteronotus parnellii, is specialized for fine frequency analysis in three narrow bands that correspond to approx 30, 60 and 90 kHz constant frequency harmonics in the biosonar signals used for Doppler-shift compensation and acoustic imaging of the environment. Previous studies have identified anatomical specializations in and around the area of the cochlea that processes the dominant second harmonic component, but similar features have not been found in areas related to sharp tuning and high sensitivity for the first or third harmonics. In this report we call attention to the large size of the tectorial membrane and spiral limbus in all three areas that appear to process the harmonically related constant frequency components. These structures are especially pronounced in the regions of the cochlea that respond to the approx 61 kHz, second harmonic and 91.5 kHz, third harmonic bands; they correspond specifically to areas where the density of afferent nerve fibers is high and where very sharply tuned neurons occur. These data for cochleae with multiple specializations lend strong support to the idea that the mass of the tectorial membrane can be an important factor in establishing the response properties of the cochlea.

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Specializations for sharp tuning in the mustached bat: The tectorial membrane and spiral limbus

Abstract

Brain Res. Rev.

Hear. Res.

Hear. Res.

Brain Res.

Hear. Res.

Hear. Res.

Hear. Res.

Science

A cochlear micromechanical model of transduction

Ear Morphology of the frog-eating bat, (Trachops cirrhosus, Family Phyllostomidae): Apparent Specializations for low-frequency hearing

J. Morph.

Inner ear structures and electrophysiological audiograms of the subterranean mole rat, Spalax ehrenbergi

Hear. Res.

Cochlear neurobiology: some key experiments and concepts of the past two decades

Vergleichende morphologische Analyse des Corti-Organs von drei Säugetierarten

Verh. Dtsch. Zool. Ges.

Comparative psychoacoustics: perspectives of peripheral sound analysis in mammals

Naturwissenschaften

Quantitative analysis of cochlear structures in the house mouse in relation to mechanisms of acoustical information processing

J. Comp. Physiol. A

Inferior colliculus of the house mouse. II. Single unit responses to tones and tone-noise combinations as a function of sound intensity

J. Comp. Physiol. A

Determination of absolute-intensity thresholds and frequency-difference thresholds in cats

J. Acoust. Soc. Am.

Die Cochlea der Säuger und der Vögel, ihre En-twicklung und ihr bau

Unusual nerve-fiber distribution in the cochlea of the bat, Pteronotus p. parnellii (Gray)

J. Acoust Soc. Am.

The basilar membrane of the bat, Pteronotus p. parnellii

Am. J. Anat.

Morphometric analysis of cochlear structures in the mustached bat, Pterortous parnelliiparnellii

A comparative study of the physiological properties of the inner ear in Doppler shift compensating bats (Rhinolophus rouxi and Pteronotus parnel-lii)

J. Comp. Physiol. A

Submicroscopic Structure of the Inner Ear

The cochlear frequency map of the mustached bat, Pteronotus parnellii

J. Comp. Physiol. A