Summary
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1.
The cochlea of the horseshoe bat,Rhinolophus ferrumequinum, was frequency mapped by exposing for 30 min to one or two continuous pure tones of intensities between 70 and 110 dB SPL. The evaluation was made by differentiating between normal and swollen nuclei of the outer hair cells (OHC) of the organ of Corti and by measuring the diameter of the nuclei of the OHC.
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2.
In control animals the radial diameter of the OHC nuclei varies systematically from a mean of 2.85 μm at the base to 3.2 um at the apex (Fig. 1).
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3.
All frequencies used for exposure were normalized to the resting frequency (FR), which is the frequency of the pure tone component of the orientation sound in a non-flying bat. The individual FR lay between 82.6 and 83.3 kHz.
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4.
For analysing the small frequencies between 83.0 to 86.0 kHz in which relevant echoes occur, 3.15 mm length of the basilar membrane is used, about the same length as for the octaves from FR/4 to FR/2 (2.85 mm) and from FR/2 to FR (3.2 mm) (Fig. Ca, b).
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5.
The discontinuity of the mechanical data at 4.5 mm of the length of the basilar membrane (part I of this paper) coincides with FR and the less pronounced discontinuity at 7.8 mm coincides with FR/2.
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6.
Location and mechanism of the auditory filter are discussed.
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References
Beck, C., Michler, H.: Feinstrukturelle und histochemische Veränderungen an der Struktur der Cochlea des Meerschweinchens nach dosierter Reintonbeschallung. Arch. Ohr.-, Nas.- u. Kehlk.- Heilk.174, 496–567 (1960)
Békésy, G. von: Über die Elastizität der Schneckentrennwand des Ohres. Akust. Z.6, 265–278 (1941)
Békésy, G. von: Über die Schwingungen der Schneckentrennwand beim Präparat aund Ohrenmodell. Akust.Z. 7, 173–186 (1942)
Brown, A.M.: High frequency peaks in the cochlear microphonic response of rodents. J. Comp. Physiol.83, 377–392 (1973a)
Brown, A.M.: High levels of responsiveness from the inferior colliculus of rodents at ultrasonic frequencies. J. Comp. Physiol.83, 393–406 (1973b)
Bruns, V.: Peripheral auditory tuning for fine frequency analysis by the CF-FM bat,Rhinolophus ferrumequinum. I. Mechanical specializations of the cochlea. J. Comp. Physiol.106, 77–86 (1976)
Evans, E.F.: Narrow “tuning” of cochlear nerve fibre responses in the guinea pig. J. Physiol. (Lond.)206, 14–15 (1970)
Evans, E.F., Wilson, J.P.: The frequency selectivity of the cochlea. In: Basic mechanisms in hearing (Møller, A.R., ed.), p. 519–554. New York: Academic Press 1973
Fernandez, C.: Dimensions of the cochlea (guinea pig). J. acoust. Soc. Amer.24, 519–523 (1952)
Geisler, C.D., Rhode, W.S., Kennedy, D.T.: Responses to tonal stimuli of single auditory nerve fibers and their relationship to basilar membrane motion in the squirrel monkey. J. Neurophysiol.37, 1156–1172 (1974)
Guild, S.R.: The width of the basilar membrane. Science65, 67–69 (1927)
Johnstone, B.M., Boyle, A.J.F.: Basilar membrane vibration examined with the Mössbauer technique. Science158, 389–390 (1967)
Kohllöffel, L.U.E.: A study of basilar membrane vibrations. I. Fuzziness-detection: a new method for the analysis of micro-vibrations with laser light. Acustica27, 49–65 (1972)
Kohllöffel, L.U.E.: Observations of the mechanical disturbances along the basilar membrane with laser illumination. In: Basic mechanisms in hearing (Møller, A.R., ed.), p. 95–117. New York: Academic Press 1973
Neubert, K.: Zur morphologischen Erfassung der Ansprechgebiete im Innenohr. Verh. Anat. Ges., 204–209 (1952)
Neubert, K., Wüstenfeld, E.: Nachweis der zellulären Ansprechgebiete im Innenohr. Naturwissenschaften11, 350–351 (1955)
Rhode, W.S.: Observations of the vibration of the basilar membrane in squirrel monkeys using the Mössbauer technique. J. acoust. Soc. Amer.49, 1218–1231 (1971)
Schnitzler, H.-U., Suga, N., Simmons, J.A.: Peripheral auditory tuning for fine frequency analysis by the CF-FM bat,Rhinolophus ferrumequinum. III. Cochlear microphonics and auditory nerve responses. J. Comp. Physiol.106, 99–110 (1976)
Steele, C.R.: Behavior of the basilar membrane with pure tone excitation. J. acoust. Soc. Amer.55, 148–162 (1974)
Suga, N., Neuweiler, G., Möller, J.: Peripheral auditory tuning for fine frequency analysis by the CF-FM bat,Rhinolophus ferrumequinum. IV. Properties of peripheral auditory neurons. J. Comp. Physiol.106, 111–125 (1976)
Tonndorf, J.: Cochlear mechanics and hydrodynamics. In: Foundations of modern auditory theory (Tobias, J.V., ed.) p. 205–254. New York: Academic Press 1970
Wilson, J.P., Johnstone, J.R.: Capacitive probe measures of basilar membrane vibration. Symposium on hearing theory, Eindhoven, IPO, 172–181 (1972)
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Supported by Stiftung Volkswagenwerk, grant No. 111858 and Deutsche Forschungsgemeinschaft, grant No. Ne 146/7.
I thank Prof. Dr. Alan D. Grinnell for discussion and his suggestions concerning the English.
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Bruns, V. Peripheral auditory tuning for fine frequency analysis by the CF-FM Bat,Rhinolophus ferrutnequinum . J. Comp. Physiol. 106, 87–97 (1976). https://doi.org/10.1007/BF00606574
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DOI: https://doi.org/10.1007/BF00606574