Hemispheric Specialization during Discrimination of Sound Sources reflected by MMN

Abstract

Event Abstract Back to Event Hemispheric Specialization during Discrimination of Sound Sources reflected by MMN Nicole Richter1, 2*, E. Schroger1 and R. Rübsamen2 1 Institute for Psychology I, University of Leipzig, Germany 2 Institute for Biology II, University of Leipzig, Germany The present study reports the hemispheric specificity of spatial auditory processing in 15 healthy subjects by measuring location-mismatch negativity (MMN) under free field stimulation. The aim was to decide between the partly inconsistent hypotheses of contralateral and/or right-hemispheric dominance in spatial processing in the auditory cortex. The laterality of deviant-standard positions were systematically varied covering the whole of the frontal hemifield from 90° left to 90° right, while the spatial separations of deviants and standards were fixed at 17°. This enabled the evaluation of the specific location-MMNs relating to distinct cortical processing of acoustic space. The inter-hemispheric comparison of the amplitudes of MMNs showed that spatial deviation towards the periphery elicited a prominent contralateral activation: Positional changes in frontal positions at -/+17° (relative to 0°-standard) elicited contralaterally higher MMN amplitudes and the respective positional changes at -/+90° (relative to -/+ 73°-standard) elicited both contralaterally pronounced MMN amplitudes and shortened MMN latencies. In contrast, positional changes towards front at -/+56° positions (relative to -/+ 73°-standard) resulted equal bilateral MMNs. Further, MMN latencies became longer with increasing laterality of respective deviant-standard pairs. Thus, the present study provides evidence for a contralateral pre-attentive cortical processing of acoustic space information in the free field. The direction of positional changes (‘towards periphery’ vs. ‘towards front’) seems to augment or reduce this contralateral effect. The sound source discrimination performance across space is also mirrored by the location-MMN latency. Conference: MMN 09 Fifth Conference on Mismatch Negativity (MMN) and its Clinical and Scientific Applications, Budapest, Hungary, 4 Apr - 7 Apr, 2009. Presentation Type: Poster Presentation Topic: Poster Presentations Citation: Richter N, Schroger E and Rübsamen R (2009). Hemispheric Specialization during Discrimination of Sound Sources reflected by MMN. Conference Abstract: MMN 09 Fifth Conference on Mismatch Negativity (MMN) and its Clinical and Scientific Applications. doi: 10.3389/conf.neuro.09.2009.05.107 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Mar 2009; Published Online: 26 Mar 2009. * Correspondence: Nicole Richter, Institute for Psychology I, University of Leipzig, Leipzig, Germany, colle@uni-leipzig.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Nicole Richter E. Schroger R. Rübsamen Google Nicole Richter E. Schroger R. Rübsamen Google Scholar Nicole Richter E. Schroger R. Rübsamen PubMed Nicole Richter E. Schroger R. Rübsamen Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.