Hemodynamic correlates of brain electrical oscillations related with working memory

Abstract

Event Abstract Back to Event Hemodynamic correlates of brain electrical oscillations related with working memory Itır Kaşıkçı1*, Ali Bayram2, 3, Esin Karahan2, Başar Bilgiç4, Ahmet Ademoğlu2 and Tamer Demiralp5 1 Istanbul University, Turkey 2 Bogazici University, Institute of Biomedical Engineering, Turkey 3 NPISTANBUL Neuropsychiatry Hospital, Turkey 4 Istanbul University, Istanbul Faculty of Medicine, Neurology Department, Turkey 5 Istanbul University, Istanbul Faculty of Medicine, Physiology Department, Turkey Majority of EEG studies related with working memory (WM) report increased amplitudes of posterior alpha and frontal theta in the retention phase and in many fMRI studies prefrontal and posterior parietal cortex activations were observed. Although posterior alpha oscillations during the retention phase might be associated with parietal regions and frontal theta oscillation with frontal regions, validity of such assumptions that do not rely on direct EEG/fMRI integration is questionable. In this study, simultaneous EEG-fMRI recordings were carried out while 18 healthy volunteers were performing a version of Sternberg paradigm. EEG signals obtained during the retention phase of WM were decomposed into topographical components using independent component analysis (ICA). Components with significantly different power between the retention phase and other phases of WM have been identified. From this set of components those that significantly differed among different memory load conditions (2/6) and the control condition were theta and alpha components with frontal distributions. The temporal courses of these components were used as regressors in fMRI analysis. Change of the frontal alpha oscillation due to WM retention phase was found correlated with fMRI activations in right orbitofrontal and dorsolateral prefrontal areas, while frontal theta was found correlated with activations in bilateral inferior temporal gyri and left inferior frontal cortex. These results shed light on the temporal dynamics of the neuronal assemblies residing in these brain areas that are closely related with memory processes. Keywords: multimodal integration, working memory Conference: XI International Conference on Cognitive Neuroscience (ICON XI), Palma, Mallorca, Spain, 25 Sep - 29 Sep, 2011. Presentation Type: Poster Presentation Topic: Poster Sessions: Multimodal Integration of EEG, MEG and fMRI data Citation: Kaşıkçı I, Bayram A, Karahan E, Bilgiç B, Ademoğlu A and Demiralp T (2011). Hemodynamic correlates of brain electrical oscillations related with working memory. Conference Abstract: XI International Conference on Cognitive Neuroscience (ICON XI). doi: 10.3389/conf.fnhum.2011.207.00096 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: 16 Nov 2011; Published Online: 25 Nov 2011. * Correspondence: Dr. Itır Kaşıkçı, Istanbul University, Istanbul, Turkey, itirk@istanbul.edu.tr 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 Itır Kaşıkçı Ali Bayram Esin Karahan Başar Bilgiç Ahmet Ademoğlu Tamer Demiralp Google Itır Kaşıkçı Ali Bayram Esin Karahan Başar Bilgiç Ahmet Ademoğlu Tamer Demiralp Google Scholar Itır Kaşıkçı Ali Bayram Esin Karahan Başar Bilgiç Ahmet Ademoğlu Tamer Demiralp PubMed Itır Kaşıkçı Ali Bayram Esin Karahan Başar Bilgiç Ahmet Ademoğlu Tamer Demiralp 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.