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: 98/5/2933    most recent 00511.2007v1 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 ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Imaizumi, K. Articles by Schreiner, C. E. Search for Related Content PubMed PubMed Citation Articles by Imaizumi, K. Articles by Schreiner, C. E.

Spatial Interaction Between Spectral Integration and Frequency Gradient in Primary Auditory Cortex

Coleman Memorial Laboratory, W. M. Keck Center for Integrative Neuroscience, Department of Otolaryngology, University of California, San Francisco, California

Submitted 7 May 2007; accepted in final form 6 September 2007

Primary sensory cortical areas are characterized by orderly and largely independent representations of several receptive field properties. This is expressed in multiple, spatially overlaying parameter distributions, such as orientation preference, spatial frequency, and ocular dominance maps in the primary visual cortex. In the auditory cortex, two main and presumably independent representational parameters are the center frequency and the frequency extent of spectral tuning curves. Here we demonstrate interactions between cortical tonotopic gradient and spectral bandwidth modules in cat primary auditory cortex (AI). First, the spatial representation of spectral integration is not equally expressed across the whole frequency range in AI. Narrow-bandwidth modules are found only in the mid-frequency region (5–20 kHz). Thus spectral integration properties delineate three frequency regions (<5, 5–20, and >20 kHz) in cat AI. Second, the extent of spectral integration covaries with the local tonotopic gradient in the low- and mid-frequency ranges. Regions with a shallow frequency gradient tend to have narrower spectral integration than those with a steep gradient. These relationships between spectral selectivity and frequency gradient constrain forebrain models of thalamo- and corticocortical convergence and connectivity and may reflect the processing of behaviorally relevant stimulus constellations.