Dynamic functional connectivity between contralateral and ipsilateral motor cortices observed using the Multi-Source Interference Task

Abstract

Event Abstract Back to Event Dynamic functional connectivity between contralateral and ipsilateral motor cortices observed using the Multi-Source Interference Task William Gaetz1*, Cheng Liu2, Hongmei Zhu2 and Timothy Roberts1 1 The Children's Hospital of Philadelphia, United States 2 York University, Department of Mathematics and Statistics, Canada Previous studies demonstrated activity of ipsilateral motor cortex and coupling at 8 -12 Hz between bilateral motor cortices during the execution of simple motor tasks [1]. In this study, we investigate the dynamic functional connectivity of brain motor areas under the Multi-Source Interference Task (MSIT) [1] using time-varying coherence analysis. The coherence function measures the linear interactions of signals from different brain areas and therefore reveals information about brain functional connectivity. However, the conventional coherence analysis assumes the stationarity of the analyzed signals, which has limited use to investigate the dynamic and transient features of brain functional activities. To better capture temporal information, we extend the definition of coherence function from the Fourier domain to the time-frequency plane using the Stockwell transform [2]. We apply this time-varying coherence analysis to a set of MEG data where a differential beamformer (dual state SAM) was used to identify contralateral (MIc) and ipsilateral motor cortices (MIi). Fifteen right-handed adult subjects (7 male, 8 female; mean ages: 31) performed the MSIT task [1] using the right hand only. For the response interference condition, we observed that subjects with significant coherence components have relatively longer response time, compared to those with almost no significant coherence. A statistical test indicates that these two groups (‘slow’ responders vs. ‘fast’) are significantly different (permutation test p<0.01). For the slow responders, the identified coupling between the MIc and MIi is concentrated in the 8-12 Hz band. Meanwhile, the Stockwell coherence also provides the time information of the onset and duration of this coupling. Our findings suggest that basic performance measures such as RT are important for observing and interpreting bi-hemispheric motor cortical interactions. Conference: Biomag 2010 - 17th International Conference on Biomagnetism , Dubrovnik, Croatia, 28 Mar - 1 Apr, 2010. Presentation Type: Poster Presentation Topic: Sensory Processing and Functional Connectivity Citation: Gaetz W, Liu C, Zhu H and Roberts T (2010). Dynamic functional connectivity between contralateral and ipsilateral motor cortices observed using the Multi-Source Interference Task. Front. Neurosci. Conference Abstract: Biomag 2010 - 17th International Conference on Biomagnetism . doi: 10.3389/conf.fnins.2010.06.00157 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 2010; Published Online: 26 Mar 2010. * Correspondence: William Gaetz, The Children's Hospital of Philadelphia, Philadelphia, United States, bill.gaetz@gmail.com 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 William Gaetz Cheng Liu Hongmei Zhu Timothy Roberts Google William Gaetz Cheng Liu Hongmei Zhu Timothy Roberts Google Scholar William Gaetz Cheng Liu Hongmei Zhu Timothy Roberts PubMed William Gaetz Cheng Liu Hongmei Zhu Timothy Roberts 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.