Summary
-
1.
Bilateral recording of cochlear potentials was used to measure the variations in interaural time differences (ITDs) and interaural intensity differences (IIDs) as a free-field auditory stimulus was moved to different positions around a barn owl's head.
-
2.
ITD varied smoothly with stimulus azimuth across a broad frequency range.
-
3.
ITD varied minimally with stimulus elevation, except at extreme angles from the horizontal.
-
4.
IID varied with both stimulus elevation and stimulus azimuth. Lower frequencies were more sensitive to variations in azimuth, whereas higher frequencies were more sensitive to variations in elevation.
-
5.
The loci of spatial coordinates that form iso-IID contours and iso-ITD contours form a nonorthogonal grid that relates binaural disparity cues to sound location.
Similar content being viewed by others
Abbreviations
- IID :
-
Interaural intensity difference
- ITD :
-
Interaural time difference
- CM :
-
Cochlear microphonic potential
References
Blauert J (1983) Spatial hearing. MIT Press, Cambridge (Mass) London
Calford MB, Pettigrew JD (1984) Frequency dependence of directional amplification at the cat's pinna. Hearing Res 14:13–19
Coles RB, Guppy A (1988) Directional hearing in the barn owl (Tyto alba). J Comp Physiol A 163:117–133
Esterly S, Knudsen EI (1987) Tuning for interaural difference cues varies with frequency for space-specific neurons in the owl's optic tectum. Neurosci Abstr 13:1468
Haresign T, Moiseff A (1988) Early growth and development of the common barn-owl's facial ruff. Auk 105:699–705
Irvine DRF (1987) Interaural intensity differences in the cat: changes in sound pressure level at the two ears associated with azimuthal displacements in the frontal horizontal plane. Hearing Res 26:267–286
Knudsen EI (1980) Sound localization in birds. In: Popper AN, Fay RR (eds) Comparative studies of hearing in vertebrates. Springer, Berlin Heidelberg New York, pp 289–322
Knudsen EI, Konishi M (1978) Space and frequency are represented separately in the auditory midbrain of the owl. J Neurophysiol 41:870–884
Knudsen EI, Konishi M (1979) Mechanisms of sound localization in the barn owl (Tyto alba). J Comp Physiol 133:13–21
Knudsen EI, Blasdel GG, Konishi M (1979) Sound localization by the barn owl (Tyto alba) measured with the search coil technique. J Comp Physiol 133:1–11
Konishi M (1973) Locatable and nonlocatable acoustic signals for barn owls. Am Nat 107:775–785
Kühne R, Lewis B (1985) External and middle ears. In: King AS, McLelland J (eds) Form and function in birds, vol 3. Academic Press, Orlando, pp 227–271
Kuwada S, Stanford TR, Batra R (1987) Interaural phase-sensitive units in the inferior colliculus of the unanesthetized rabbit: effects of changing frequency. J Neurophysiol 57:1338–1360
Lewis B (1983) Directional cues for auditory localisation. In: Lewis B (ed) Bioacoustics. Academic Press, London, pp 233–257
Moiseff A (1989) Bi-coordinate sound localization by the barn owl. J Comp Physiol A 164:637–644
Moiseff A, Konishi M (1981) Neuronal and behavior sensitivity to binaural time difference in the owl. J Neurosci 1:40–48
Moiseff A, Konishi M (1983) Binaural characteristics of units in the barn owl's brainstem auditory pathway: Precursors of restricted spatial receptive fields. J Neurosci 3:2553–2562
Norberg RÅ (1978) Skull asymmetry, ear structure and function, and auditory localization in Tengmalm's owl,Aegolius funerus (L.). Phil Trans R Soc Lond B 282:325–410
Payne RS (1971) Acoustic location of prey by barn owls (Tyto alba). J Exp Biol 54:535–573
Sullivan WE, Konishi M (1984) Segregation of stimulus phase and intensity coding in the cochlear nucleus of the barn owl. J Neurosci 4:1787–1799
Takahashi T, Konishi M (1986) Selectivity for interaural time difference in the owl's midbrain. J Neurosci 6:3413–3422
Takahashi T, Moiseff A, Konishi M (1984) Time and intensity cues are processed independently in the auditory system of the owl. J Neurosci 4:1781–1786
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Moiseff, A. Binaural disparity cues available to the barn owl for sound localization. J. Comp. Physiol. 164, 629–636 (1989). https://doi.org/10.1007/BF00614505
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00614505