Oscillatory mechanism of auditory stream segregation in primary auditory cortex

Abstract

Event Abstract Back to Event Oscillatory mechanism of auditory stream segregation in primary auditory cortex Peter Lakatos1*, Noelle OConnell1, Arnaud Falchier1 and Charles E. Schroeder1 1 Nathan Kline Institute for Psychiatric Research, Cognitive Neuroscience and Schizophrenia Program, United States Earlier studies show that neuronal oscillations reflecting rhythmic excitability fluctuations of neuronal ensembles can track rhythmic stimulus streams by entraining to their temporal structure. When stimuli are most likely to occur, neuronal ensembles are consistently in high excitability phases resulting in an amplification of neuronal responses to events. At the same time, entrained oscillations also serve as temporal filters, in that their low excitability phases suppress neuronal responses to events that are "out of phase" with the attended stream. In theory, this makes entrained oscillations ideal candidates to separate attended rhythmic streams from the background in complex auditory scenes. We examined laminar profiles of synaptic activity and action potentials obtained through multielectrode recordings in monkey A1. We presented two concurrent streams of pure tones that differed in their rhythm and frequency. Subjects responded to deviants in only one of the streams, while ignoring deviants in the other. We found that neuronal oscillations across A1 entrained to the rhythm of the attended stream, even in regions whose best frequency (BF) matched that of pure tones in the ignored stream. We also found that entrainment was frequency specific: if the frequency of pure tones in the attended stream corresponded to the BF of a given A1 region, oscillations entrained with their high, while outside this region oscillations entrained with their low excitability phases. This indicates that entrained oscillations across A1 act as a complex spectral-temporal filter mechanism, making them ideal candidates for the segregation of relevant rhythmic auditory stimulus streams along arguably the most fundamental organizing dimensions in auditory processing, frequency and time. Keywords: auditory processing, neuronal oscillations Conference: XI International Conference on Cognitive Neuroscience (ICON XI), Palma, Mallorca, Spain, 25 Sep - 29 Sep, 2011. Presentation Type: Symposium: Oral Presentation Topic: Symposium 3: The role of neuronal oscillations in computation and communication in multi-scale brain networks Citation: Lakatos P, OConnell N, Falchier A and Schroeder CE (2011). Oscillatory mechanism of auditory stream segregation in primary auditory cortex. Conference Abstract: XI International Conference on Cognitive Neuroscience (ICON XI). doi: 10.3389/conf.fnhum.2011.207.00021 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: 04 Nov 2011; Published Online: 15 Nov 2011. * Correspondence: Dr. Peter Lakatos, Nathan Kline Institute for Psychiatric Research, Cognitive Neuroscience and Schizophrenia Program, Orangeburg, NY, 10962, United States, plakatos@nki.rfmh.org 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 Peter Lakatos Noelle OConnell Arnaud Falchier Charles E Schroeder Google Peter Lakatos Noelle OConnell Arnaud Falchier Charles E Schroeder Google Scholar Peter Lakatos Noelle OConnell Arnaud Falchier Charles E Schroeder PubMed Peter Lakatos Noelle OConnell Arnaud Falchier Charles E Schroeder 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.