| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Physiology, University of Wisconsin, Madison, WI, USA
* To whom correspondence should be addressed. E-mail: tollin{at}physiology.wisc.edu.
Several auditory spatial illusions, collectively called the precedence effect (PE), occur when transient sounds are presented from two different spatial locations, but separated in time by an inter-stimulus delay (ISD). For ISDs in the range of localization dominance (< 10 ms), a single fused sound is typically located near the leading source location only, as if the location of the lagging source were suppressed. For longer ISDs, both the leading and lagging sources can be heard and localized, and the shortest ISD where this occurs is called the echo threshold. Previous physiological studies of the extracellular responses of single neurons in the inferior colliculus (IC) of anesthetized cats and unanesthetized rabbits with sounds known to elicit the PE have shown correlates of these phenomena though there were differences in the physiologically-measured echo thresholds. Here we recorded in the IC of awake, behaving cats using stimuli that we have shown to evoke behavioral responses that are consistent with the precedence effect (Tollin and Yin, 2003; J Neurophysiol 90: 2149-2162). For small ISDs responses to the lag were reduced or eliminated, consistent with psychophysical data showing that sound localization is based on the leading source, or localization dominance. At longer ISDs, the responses to the lagging source recovered at ISDs comparable to psychophysically-measured echo thresholds. Thus it appears that anesthesia, and not species differences, accounts for the discrepancies in the earlier studies.
This article has been cited by other articles:
|
|
 |
|
  M. Ter-Mikaelian, D. H. Sanes, and M. N. Semple Transformation of Temporal Properties between Auditory Midbrain and Cortex in the Awake Mongolian Gerbil J. Neurosci., June 6, 2007; 27(23): 6091 - 6102. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Pecka, T. P. Zahn, B. Saunier-Rebori, I. Siveke, F. Felmy, L. Wiegrebe, A. Klug, G. D. Pollak, and B. Grothe Inhibiting the Inhibition: A Neuronal Network for Sound Localization in Reverberant Environments J. Neurosci., February 14, 2007; 27(7): 1782 - 1790. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. W. Spitzer and T. T. Takahashi Sound Localization by Barn Owls in a Simulated Echoic Environment J Neurophysiol, June 1, 2006; 95(6): 3571 - 3584. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Schuchmann, M. Hubner, and L. Wiegrebe The absence of spatial echo suppression in the echolocating bats Megaderma lyra and Phyllostomus discolor J. Exp. Biol., January 1, 2006; 209(1): 152 - 157. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. C. Populin Anesthetics Change the Excitation/Inhibition Balance That Governs Sensory Processing in the Cat Superior Colliculus J. Neurosci., June 22, 2005; 25(25): 5903 - 5914. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
