HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 96/2/813    most recent 01144.2005v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by Gutfreund, Y. Articles by Knudsen, E. I. Search for Related Content PubMed PubMed Citation Articles by Gutfreund, Y. Articles by Knudsen, E. I.

Adaptation in the Auditory Space Map of the Barn Owl

Department of Neurobiology, Stanford University, Stanford, California

Submitted 31 October 2005; accepted in final form 3 May 2006

Auditory neurons in the owl’s external nucleus of the inferior colliculus (ICX) integrate information across frequency channels to create a map of auditory space. This study describes a powerful, sound-driven adaptation of unit responsiveness in the ICX and explores the implications of this adaptation for sensory processing. Adaptation in the ICX was analyzed by presenting lightly anesthetized owls with sequential pairs of dichotic noise bursts. Adaptation occurred in response even to weak, threshold-level sounds and remained strong for more than 100 ms after stimulus offset. Stimulation by one range of sound frequencies caused adaptation that generalized across the entire broad range of frequencies to which these units responded. Identical stimuli were used to test adaptation in the lateral shell of the central nucleus of the inferior colliculus (ICCls), which provides input directly to the ICX. Compared with ICX adaptation, adaptation in the ICCls was substantially weaker, shorter lasting, and far more frequency specific, suggesting that part of the adaptation observed in the ICX was attributable to processes resident to the ICX. The sharp tuning of ICX neurons to space, along with their broad tuning to frequency, allows ICX adaptation to preserve a representation of stimulus location, regardless of the frequency content of the sound. The ICX is known to be a site of visually guided auditory map plasticity. ICX adaptation could play a role in this cross-modal plasticity by providing a short-term memory of the representation of auditory localization cues that could be compared with later-arriving, visual–spatial information from bimodal stimuli.

This article has been cited by other articles:

				J. F. Bergan and E. I. Knudsen Visual Modulation of Auditory Responses in the Owl Inferior Colliculus J Neurophysiol, June 1, 2009; 101(6): 2924 - 2933. [Abstract] [Full Text] [PDF]

				Y. Zahar, A. Reches, and Y. Gutfreund Multisensory Enhancement in the Optic Tectum of the Barn Owl: Spike Count and Spike Timing J Neurophysiol, May 1, 2009; 101(5): 2380 - 2394. [Abstract] [Full Text] [PDF]

				A. Kohn Visual Adaptation: Physiology, Mechanisms, and Functional Benefits J Neurophysiol, May 1, 2007; 97(5): 3155 - 3164. [Abstract] [Full Text] [PDF]