Abstract
The aim of this study was to gain information from anesthetized cats about the differential coding properties of neurons in the three major subdivisions of the inferior colliculus: the central (CNIC) and external (EN) nuclei and dorsal cortex (DC). Stimuli were presented in the free field from a speaker facing the contralateral pinna. For each unit, the characteristic frequency (CF, where threshold was lowest) was determined, and impulse rates to CF tone bursts, noise bursts and four feline vocal stimuli were measured as a function of increasing sound pressure level (rate/level functions). Peristimulus-time histograms were computed for responses to all stimuli. Sustained firing patterns to CF stimuli were observed for 81% of units in CNIC, for 50% of units in EN and 27% of units in DC. Sustained discharges were evoked by noise in 78–100% of units in all regions, and by at least one vocal stimulus in 86% of units in CNIC, 82% in EN and 55% in DC. In the CNIC, non-monotonic rate/level functions to CF stimuli were more common (41%) than either monotonie or plateau functions, whereas the reverse was the case with noise and vocal stimuli. Non-monotonic functions were uncommon to any stimulus in EN and DC (21–24%). Vocal stimuli were more effective in terms of higher firing rates than noise or CF stimuli in 27% of units in CNIC, 82% in EN and 72% in DC. There were no units that responded exclusively to one vocal stimulus, but a high proportion of units in EN responded strongly to broad band stimuli, and some of these showed clear preferences for one vocal stimulus over others.
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References
Aitkin LM (1986) The auditory midbrain. Humana, Clifton NJ
Aitkin LM (1990) The auditory cortex. Chapman & Hall, London
Aitkin L (1991) Rate-level functions of neurons in the inferior colliculus of cats measured with the use of free-field sound stimuli. J Neurophysiol 65:383–392
Aitkin LM, Boyd J (1978) Acoustic input to the lateral pontine nuclei. Hear Res 1:67–77
Aitkin LM, Webster WR, Veale JL, Crosby DC (1975) Inferior colliculus. I. Comparison of response properties of neurons in the central, pericentral, and external nuclei of adult cat. J Neurophysiol 38:1196–1207
Aitkin LM, Dickhaus H, Schult W, Zimmermann M (1978) External nucleus of inferior colliculus: auditory and spinal somatosensory afferents and their interactions. J Neurophysiol 1:837–847
Aitkin LM, Kenyon CE, Philpott P (1981) The representation of the auditory and somatosensory systems in the external nucleus of the cat inferior colliculus. J Comp Neurol 196:25–40
Aitkin LM, Pettigrew JD, Calford MB, Phillips SC, Wise LZ (1985) Representation of stimulus azimuth by low-frequency neurons in inferior colliculus of the cat. J Neurophysiol 53:43–59
Altafullah I, Shipley C, Buchwald JS (1988) Voiced calls evoked by hypothalamic stimulation in the cat. Exp Brain Res 71:21–32
Berman AL (1968) The brainstem of the cat. A cytoarchitectonic atlas with stereotaxic co-ordinates. University of Wisconsin Press, Madison
Brown KA, Buchwald JS, Johnson JR, Mikholich DJ (1978) Vocalization in the cat and kitten. Dev Psychobiol 11:559–570
Calford MB, Webster WR, Semple MN (1983) Measurement of frequency selectivity of single neurons in the central auditory pathway. Hear Res 11:395–401
Dewson JH (1964) Speech discrimination by cats. Science 144:555–556
Ehret G, Merzenich MM (1988) Complex sound analysis (frequen-cy resolution, filtering and spectral integration) by single units of the inferior colliculus of the cat. Brain Res Rev 13:139–163
Farley GR, Barlow SM, Netsell R, Chmelka JV (1992a) Vocalizations in the cat: behavioral methodology and spectrographic analysis. Exp Brain Res 89:333–340
Farley GR, Barlow SM, Netsell R (1992b) Factors influencing neural activity in parabrachial regions during cat vocaliza-tions. Exp Brain Res 89:341–351
Hashikawa T, Kawamura K (1983) Retrograde labeling of ascend ing and descending neurons in the inferior colliculus. A fluo-rescent double-labeling study in the cat. Exp Brain Res 49:457–461
Heffner HE, Heffner RS (1986) Effect of unilateral and bilateral auditory cortex lesions on the discrimination of vocalizations by Japanese macaques. J Neurophysiol 56:683–701
Hupfer J, Jürgens U, Ploog D (1979) The effects of superior temporal lesions on the recognition of species-specific calls in the squirrel monkey. Exp Brain Res 30:75–87
Imig TJ, Morel A (1988) Organization of the cat's auditory thalamus. In: Edelman GM, Gall WE, Cowan WM (eds) Auditory function. Wiley, New York, pp 457–484
Irvine DRF (1986) The auditory brainstem. In: Ottoson D (eds) Progress in sensory physiology, vol 7. Springer, Berlin Heidelberg New York, pp 1–279
Kawamura K (1975) The pontine projection from the inferior colliculus in the cat. An experimental anatomical study. BrainRes 95:309–322
Kudo M, Aitkin LM, Nelson JE (1989) Auditory forebrain organization of an Australian marsupial, the northern native cat (Dasyurus hallucatus). J Comp Neurol 279:28–42
de Lanerolle NC, Lang FF (1988) Functional neural pathways for vocalization in the domestic cat. In: Newman JD (ed) The physiological control of mammalian vocalization. Plenum Press, New York, pp 21–41
Langner G, Schreiner CE (1988) Periodicity coding in the inferior colliculus of the cat. I. Neuronal mechanisms. J Neurophysiol 60:1799–1822
Merzenich MM, Reid MD (1974) Representation of the cochlea within the inferior colliculus of the cat. Brain Res 77:397–415
Morest DK, Oliver DL (1984) The neuronal architecture of the inferior colliculus in the cat: defining the functional anatomy of the auditory midbrain. J Comp Neurol 222:209–236
Nelson PG, Erulkar SD, Bryan JS (1966) Responses of units of the inferior colliculus to time-varying acoustic stimuli. J Neurophysiol 29:834–860
Oliver DL, Kuwada S, Yin TCT, Haberly LB, Henkel CK (1991) Dendritic and axonal morphology of HRP-injected neurons in the inferior colliculus of the cat. J Comp Neurol 303:75–100
Poon PWF, Chen X, Hwang JC (1991) Basic determinants for FM responses in the inferior colliculus of rats. Exp Brain Res 83:598–606
Reale RA, Imig TJ (1983) Auditory cortical field projections to the basal ganglia of the cat. Neuroscience 8:67–86
Rees A, Møller AR (1983) Responses of neurons in the inferior colliculus of the rat to AM and FM tones. Hear Res 10:301–330
Rees A, Møller AR (1987) Stimulus properties influencing the responses of inferior colliculus neurons to amplitude-modulated sounds. Hear Res 27:129–143
Riquimaroux H, Gaioni SJ, Suga N (1991) Cortical computation-al maps control auditory perception. Science 251:565–568
Rockel AJ, Jones EG (1973) The neuronal organization of the inferior colliculus of the adult cat. I. The central nucleus. J Comp Neurol 147:11–60
Rose JE, Greenwood DD, Goldberg JM, Hind JE (1963) Some discharge characteristics of single neurons in the inferior colliculus of the cat. I. Tonotopical organization, relation of spike-counts to tone intensity, and firing patterns of single elements. J Neurophysiol 26:294–320
Schreiner CE, Langner G (1988) Periodicity coding in the inferior colliculus of the cat. II. Topographical organization. J Neurophysiol 60:1823–1840
Semple MN, Aitkin LM (1979) Representation of sound frequency and laterality by units in central nucleus of cat inferior colliculus. J Neurophysiol 42:1626–1639
Smolders JWT, Aertsen AMH, Johannesma PIM (1979) Neural representation of the acoustic biotope. Biol Cybern 35:11–20
Syka J, Straschill M (1970) Activation of superior colliculus neurons and motor responses after electrical stimulation of the inferior colliculus. Exp Neurol 28:384–392
Symmes D (1981) On the use of natural stimuli in neurophysiological studies of audition. Hear Res 4:203–214
Watanabe T (1972) Fundamental study of the neural mechanism in cats subserving the feature extraction process of complex sounds. Jpn J Physiol 22:569–583
Watanabe T, Katsuki Y (1974) Response patterns of single auditory neurons of the cat to species-specific vocalization. Jpn J Physiol 24:135–155
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Aitkin, L., Tran, L. & Syka, J. The responses of neurons in subdivisions of the inferior colliculus of cats to tonal, noise and vocal stimuli. Exp Brain Res 98, 53–64 (1994). https://doi.org/10.1007/BF00229109
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DOI: https://doi.org/10.1007/BF00229109