Directed information flow during the retention phase of visuospatial working memory

Abstract

Event Abstract Back to Event Directed information flow during the retention phase of visuospatial working memory Hyojin Park1*, June S. Kim2, Eunjoo Kang3, Hyekyoung Lee1, Chun-Kee Chung4 and Dong S. Lee1 1 Seoul National University College of Medicine, Department of Nuclear Medicine, South Korea 2 Seoul National University Hospital, MEG Center, Department of Neurosurgery, South Korea 3 Kangwon National University, Department of Psychology, South Korea 4 Seoul National University College of Medicine, MEG Center, Department of Neurosurgery, South Korea Measures of functional interaction can provide more exact insights into how the brain works by characterizing the direction of information flow between brain regions. Although a lot of insight has been gained into the brain regions involved in the retention of spatial working memory and their connectivity patterns, the directional influence between them remains unclear. Thus, we estimated causal connectivity between cortical regions from MEG data examined during the retention phase of spatial working memory. Data recorded by a VectorView MEG system from subjects performing a spatial working memory task was analyzed in the frequency domain. After source reconstruction using a beamforming technique from memory dependent power increases in alpha, beta, and gamma ranges, we defined the regions of interest: left superior frontal gyrus(BA9), right middle frontal gyrus(BA9), left middle frontal gyrus(BA8), right middle frontal gyrus(BA6), right superior temporal gyrus(BA42), left fusiform gyrus(BA19), right lingual gyrus(BA18) and left cerebellum. To identify information flow between the sources, we used PDC(partial directed coherence), a frequency domain measure of Granger causality, to quantify effective connectivity. PDC is particularly of interest when it comes to its ability to reveal direct influences by partializing out indirect connections. As preliminary results, the main findings are as follows: PDC detected information flow from bilateral frontal regions to right superior temporal gyrus, and from left cerebellum to right superior gyrus, left fusiform gyrus, and right lingual gyrus. Left fusiform gyrus and right lingual gyrus were found to receive information from all other regions. The present study showed how brain regions involved in updating and maintaining spatial information are dynamically connected. The pattern of causal influences found primarily suggests a flow of information from frontal to superior temporal areas most likely reflecting top-down influence. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Poster Presentation Topic: Neurocognition and Functional Connectivity Citation: Park H, Kim JS, Kang E, Lee H, Chung C and Lee DS (2010). Directed information flow during the retention phase of visuospatial working memory. Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00426 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: 09 Apr 2010; Published Online: 09 Apr 2010. * Correspondence: Hyojin Park, Seoul National University College of Medicine, Department of Nuclear Medicine, Seoul, South Korea, hjpark05@snu.ac.kr 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 Hyojin Park June S Kim Eunjoo Kang Hyekyoung Lee Chun-Kee Chung Dong S Lee Google Hyojin Park June S Kim Eunjoo Kang Hyekyoung Lee Chun-Kee Chung Dong S Lee Google Scholar Hyojin Park June S Kim Eunjoo Kang Hyekyoung Lee Chun-Kee Chung Dong S Lee PubMed Hyojin Park June S Kim Eunjoo Kang Hyekyoung Lee Chun-Kee Chung Dong S Lee 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.