Summary
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1.
Neurones in the auditory midbrain nucleus (MLD) of Guinea Fowl were examined for specific encoding of vocalizations. Single units were recorded in chronic awake preparations of birds. The animals were presented with various artificial stimuli and tape recordings of conspecific calls.
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2.
Several Guinea Fowl vocalizations are characterized by multiple-line spectra or by inhomogeneous noise components (Fig. 4). Such broad energy distributions were called ‘frequency complexes’. Neuronal preference particularly of calls which contained frequency complexes was examined by three methods: (a) Use of natural variations of calls; (b) selective filtering of calls; (c) technical synthesis of complex components of calls.
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3.
Of the neurones in the material, 60% showed responses to complex stimuli not simply predictable from pure tone responses (complex neurones). None of the neurons gave exclusive responses to a particular call but some preferred certain calls. Several types of complex neurones were distinguished which might be considered suitable for the detection of frequency complexes in calls.
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4.
Units with broad inhibitory bands in response to pure tones were excited by harmonic (pulse) spectra or other frequency combinations which fell into the inhibitory band (Figs. 4–6). Similarly units with weak but wide-band excitation by pure tones often responded to multiple-line spectra (Fig. 6).
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5.
Neurones with preference for several tone frequencies favoured spectra which overlapped those optimal frequencies (Fig. 3).
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6.
FM sensitivity was seen in combination with preference for frequency complexes (Fig. 8).
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References
Abeles, M., Goldstein, M.H.: Functional architecture in cat primary auditory cortex: Columnar organization and organization according to depth. J. Neurophysiol.33, 172–187 (1970)
Biederman-Thorson, M.: Auditory responses of neurones in the lateral mesencephalic nucleus (inferior colliculus) of the Barbary Dove. J. Physiol. (Lond.)193, 695–705 (1967)
Brown, J.L.: The control of avian vocalization by the central nervous system. In: Bird vocalization (ed. R.A. Hinde), pp. 79–96. Cambridge: Cambridge University Press 1969
Evans, E.F.: Cortical representation. In: Hearing mechanisms in vertebrates (ed. A.V.S. de Reuck, J. Knight), pp. 272–287. London: Churchill Ltd. 1968
Evans, E.F.: Central mechanisms relevant to the neural analysis of simple and complex sounds. In: Pattern recognition in biological and technical systems, pp. 328–343. Berlin-Heidelberg-New York: Springer 1971
Evans, E.F., Whitfield, I.C.: Classification of unit responses in the auditory cortex of the unanesthetized and unrestrained cat. J. Physiol. (Lond.)171, 476–493 (1964)
Frishkopf, L.S., Capranica, R.R., Goldstein, M.H., Jr.: Neural coding in the bullfrog's auditory system—a teleological approach. Proc. IEEE56, 969–980 (1968)
Funkenstein, H.H., Winter, P.A.: Responses to acoustic stimuli of units in the auditory cortex of awake squirrel monkeys. Exp. Brain Res.18, 464–488 (1973)
Galambos, R.: Studies of the auditory system with implanted electrodes. In: Neural mechanisms of the auditory and vestibular system (eds. G.L. Rasmussen, W.F. Windle), pp. 137–151. Springfield: C.C. Thomas 1960
Goldstein, J.L., Hall, J.L., Butterfield, B.O.: Single unit activity in primary auditory cortex of unanesthetized cats. J. acoust. Soc. Amer.43, 444–455 (1968)
Greenewalt, C.H.: Bird song: Acoustics and physiology. City of Washington: Smithsonian Institution Press 1968
Kallert, S., David, E., Finkenzeller, P., Keidel, W.D.: Two different neuronal discharge periodicities in the acoustic channel. In: Frequency analysis and periodicity detection in hearing (eds. R. Plomp, G.F. Smoorenburg), pp. 115–122. Leiden: Sijthoff 1971
Karten, H.J.: The organization of the ascending auditory pathway in the pigeon (Columba livia). I. Diencephalic projections of the inferior colliculus (Nucleus mesencephalicus lateralis, pars dorsalis). Brain Res.6, 409–427 (1967)
Karten, H.J.: The ascending auditory pathway in the pigeon (Columba livia). II. Telecephalic projections of the nucleus ovoidalis thalami. Brain Res.11, 134–153 (1968)
Leppelsack, H.J.: Funktionelle Eigenschaften der Hörbahn im Feld L des Neostriatum caudale des Staren (Sturnus vulgaris L., Aves). J. comp. Physiol.88, 271–320 (1974)
Leppelsack, H.J., Vogt, M.: Responses of auditory neurons in the forebrain of a songbird to stimulation with species-specific sounds. J. comp. Physiol.107, 263–274 (1976)
Merzenich, M.M., Knight, P.L., Roth, G.L.: Representation of cochlea within primary auditory cortex in the cat. J. Neurophysiol.38, 231–249 (1975)
Neuweiler, G.: Frequenzdiskriminierung in der Hörbahn von Säugern. Verh. dtsch. Zool.66, 168–176 (1973)
Newman, J.D., Wollberg, Z.: Multiple coding of species-specific vocalizations in the auditory cortex of squirrel monkeys. Brain Res.54, 287–304 (1973)
Nottebohm, F.: The origin of vocal learning. Amer. Naturalist106, 116–140 (1972)
Oonishi, S., Katsuki, Y.: Functional organization and integrative mechanism in the auditory cortex of the cat. Jap. J. Physiol.15, 342–365 (1965)
Scheich, H.: Central processing of complex sounds and feature analysis. In: Dahlem Workshop on: Recognition of complex acoustic signals (ed. T.H. Bullock). Berlin: in press 1977
Sovijärvi, A.R.A.: Single neuron responses to complex and moving sounds in the primary auditory cortex of the cat. Thesis, Medical Faculty of the University of Helsinki (1973)
Stopp, Ph.E., Whitfield, I.C.: Unit responses from brainstem nuclei in the pigeon. J. Physiol. (Lond.)158, 165–177 (1961)
Suga, N.: Analysis of frequency modulated sounds by auditory neurones of echolocating bats. J. Physiol. (Lond.)179, 26–53 (1965)
Suga, N.: Classification of inferior collicular neurones of bats in terms of responses to pure tones, FM sounds and noise bursts. J. Physiol. (Lond.)200, 555–574 (1969)
Suga, N.: Feature extraction in the auditory system of bats. In: Basic mechanisms in hearing (ed. A.R. Møller), pp. 675–744. Academic Press 1973
Watanabe, T., Katsuki, Y.: Response patterns of single auditory neurons of the cat to species-specific vocalizations. Jap. J. Physiol.24, 135–155 (1974)
Wever, E.G.: Theory of Hearing. New York: Wiley 1949
Whitfield, J.C., Evans, E.F.: Responses of auditory cortical neurons to stimuli of changing frequency. J. Neurophysiol.28, 655–672 (1965)
Winter, P.A., Funkenstein, H.H.: The effect of species-specific vocalizations on the discharge of auditory cortical cells in the awake squirrel monkey (Saimiri sciureus). Exp. Brain Res.18, 489–504 (1973)
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Supported by the Deutsche Forschungsgemeinschaft
I wish to thank Dr. R. Oades for critical reading of the manuscript.
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Scheich, H., Langner, G. & Koch, R. Coding of narrow-band and wide-band vocalizations in the auditory midbrain nucleus (MLD) of the Guinea Fowl (Numida meleagris). J. Comp. Physiol. 117, 245–265 (1977). https://doi.org/10.1007/BF00612789
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DOI: https://doi.org/10.1007/BF00612789