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Fast realistic modeling in bioelectromagnetism using lead-field interpolation

Blaise Yvert, Anne Crouzeix-Cheylus, Jacques Pernier
2001 Human Brain Mapping  
Illustrated with the BEM for EEG and MEG, it applies to ECG and MCG as well. The principle is two-fold.  ...  Cropping grids by removing shallow points lead to a much better estimation of the dipole orientation in EEG than when solving the forward problem classically, providing an efficient alternative to locally  ...  ACKNOWLEDGMENTS This work was supported in part by a grant from the Fyssen Foundation (Paris) awarded to B.Y.  ... 
doi:10.1002/hbm.1041 pmid:11500990 fatcat:kyx3o5e3qjg4nmucazdov4l4ny

On the fully automatic construction of a realistic head model for EEG source localization

Qaiser Mahmood, Yazdan Shirvany, Andrew Mehnert, Artur Chodorowski, Johanna Gellermann, Fredrik Edelvik, Anders Hedstrom, Mikael Persson
2013 2013 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)  
ACKNOWLEDGMENT The authors would like to thank Simon Bergstrand for his participation as the healthy subject in this study.  ...  EEG Source Localization Given a FEHCM the EEG source localization procedure involves the solution of the following two problems: (i) the forward problem which deals with finding the scalp potentials for  ...  of a realistic FEHCM for EEG source localization.  ... 
doi:10.1109/embc.2013.6610254 pmid:24110441 dblp:conf/embc/MahmoodSMCGEHP13 fatcat:4nmvpbeumffrbf7hnxwpfj2rt4

Validation of the Two-Level Approach for the Solution of the EEG Inverse Problem in an Anisotropic Realistic Head Model

G. Crevecoeur, H. Hallez, L. Dupre, R. Van de Walle, P. Boon, I. Lemahieu
2009 IEEE transactions on magnetics  
The EEG source localization procedure requires the solution of an inverse problem.  ...  Results obtained from the EEG source localization are compared with measurements of depth electrodes. The results show the fast localization and noise robustness of the numerical procedure.  ...  The authors would like to thank the Department of Neurology, Ghent University, for the data and their cooperation.  ... 
doi:10.1109/tmag.2009.2012773 fatcat:rfevnkhrkfbldgis5p3i3aux44

The FieldTrip-SimBio pipeline for EEG forward solutions

Johannes Vorwerk, Robert Oostenveld, Maria Carla Piastra, Lilla Magyari, Carsten H. Wolters
2018 BioMedical Engineering OnLine  
Accurately solving the electroencephalography (EEG) forward problem is crucial for precise EEG source analysis.  ...  The accuracy with which the EEG forward problem can thereby be solved is increased compared to the commonly used threecompartment head models, and more reliable EEG source reconstruction results can be  ...  The finite element method for solving the EEG forward problem The presented pipeline employs a Lagrange (or continuous Galerkin) FEM approach, as it is commonly used for solving the EEG forward problem  ... 
doi:10.1186/s12938-018-0463-y pmid:29580236 pmcid:PMC5870695 fatcat:ojkipxj44zeojpm2ixjsxtrhma

EEG Signals based Brain Source Localization Approaches

Anwar Ali Gaho, Sayed Hyder, Munsif Ali, Muhammad Shafiq
2018 International Journal of Advanced Computer Science and Applications  
In this paper, several approaches of forward problem, inverse problem and Bayesian framework have been explored to address the uncertainties and issues of localization of the neural activities incurring  ...  This article is focused on the overview of functionality of the neurons and investigation of the current research and algorithms used for brain source localization.  ...  EEG SOURCE LOCALIZATION ALGORITHIMS The forward and inverse problems are used for locating the sources of the brain activity.  ... 
doi:10.14569/ijacsa.2018.090934 fatcat:bdn5pncoo5eupjhj7hk47jwtvu

Age-Related EEG Power Reductions Cannot Be Explained by Changes of the Conductivity Distribution in the Head Due to Brain Atrophy

Mingjian He, Feng Liu, Aapo Nummenmaa, Matti Hämäläinen, Bradford C. Dickerson, Patrick L. Purdon
2021 Frontiers in Aging Neuroscience  
To address this ambiguity, we employed EEG forward models to investigate whether brain shrinkage is a major factor for the signal attenuation in the aging brain.  ...  We simulated brain shrinkage in spherical and realistic brain models and found that changes in the conductor geometry cannot fully account for the EEG power reductions even when the brain was shrunk to  ...  ACKNOWLEDGMENTS The authors would like to thank Matti Stenroos for guidance of using the Helsinki BEM solver for the realistic volume conductor models.  ... 
doi:10.3389/fnagi.2021.632310 pmid:33679380 pmcid:PMC7929986 fatcat:7lof5at77zhwjdyfqgxwghn3tu

Using reciprocity for relating the simulation of transcranial current stimulation to the EEG forward problem [article]

Sven Wagner, Felix Lucka, Johannes Vorwerk, Christoph Herrmann, Guido Nolte, Martin Burger, Carsten H. Wolters
2016 bioRxiv   pre-print
It is then proven that AA and PI are also algebraically identical even for general head models. This relation offers a direct link between the EEG forward problem and tCS.  ...  direct EEG forward approach for dipolar primary current sources both based on the finite element method (FEM), namely the adjoint approach (AA) and the partial integration approach in conjunction with  ...  Acknowledgement This work has been supported by the priority program SPP1665 of the German Research Foundation, projects WO1425/5-1 (for SW, FL, JV, MB and CHW), HE3353/8-1 (for CSH) and EN533/13-1 (for  ... 
doi:10.1101/043554 fatcat:mgbywr225ng77mcbhwaoiyznjq

Comparison of Boundary Element and Finite Element Approaches to the EEG Forward Problem

J. Vorwerk, M. Clerc, M. Burger, C. H. Wolters
2012 Biomedical Engineering  
The accurate simulation of the electric fields evoked by neural activity is crucial for solving the inverse problem of EEG.  ...  In this study we compare the accuracy and performance of state-of-the-art BE and FE approaches in both artificial and realistic three layer head models, showing that all approaches lead to high numerical  ...  To solve this problem, the accurate simulation of the electric field evoked by dipole sources in the brain is crucial.  ... 
doi:10.1515/bmt-2012-4152 pmid:23096316 fatcat:xobum46dpfbkrj7ibnn2aknati

Using reciprocity for relating the simulation of transcranial current stimulation to the EEG forward problem

S. Wagner, F. Lucka, J. Vorwerk, C.S. Herrmann, G. Nolte, M. Burger, C.H. Wolters
2016 NeuroImage  
It is then proven that AA and PI are also algebraically identical even for general head models. This relation offers a direct link between the EEG forward problem and tCS.  ...  direct EEG forward approach for dipolar primary current sources both based on the finite element method (FEM), namely the adjoint approach (AA) and the partial integration approach in conjunction with  ...  Acknowledgement This work has been supported by the priority program SPP1665 of the German Research Foundation, projects WO1425/5-1 (for SW, FL, JV, MB and CHW), HE3353/8-1 (for CSH) and EN533/13-1 (for  ... 
doi:10.1016/j.neuroimage.2016.04.005 pmid:27125841 fatcat:34zny6sxs5hhdipxg6utc3w3lu

Solving High-Resolution Forward Problems for Extra- and Intracranial Neurophysiological Recordings Using Boundary Element Fast Multipole Method [article]

Sergey N Makarov, Matti Hämäläinen, Yoshio Okada, Gregory Noetscher, Jyrki Ahveninen, Aapo Nummenmaa
2019 bioRxiv   pre-print
We present a general numerical approach for solving the forward problem in high−resolution.  ...  and (iv) taking into account the effect a fontanel for infant EEG source modeling and comparison of the results with a commercially available FEM.  ...  Leslie Greengard of the Courant Institute of Mathematical Sciences, New York, NY for multiple insightful discussions and support in our utilization of the  ... 
doi:10.1101/567933 fatcat:pardvcpuz5fqzh6emz3bfrspru

Accuracy of Two Dipolar Inverse Algorithms Applying Reciprocity for Forward Calculation

Päivi Laarne, Jari Hyttinen, Silke Dodel, Jaakko Malmivuo, Hannu Eskola
2000 Computers and Biomedical Research  
Two inverse algorithms were applied for solving the EEG inverse problem assuming a single dipole as a source model.  ...  This method provides a procedure to calculate the computationally heavy forward problem by a single solution for each EEG lead.  ...  ACKNOWLEDGMENTS The authors acknowledge the contribution of P. Ryymin, Tampere University Hospital, and T. Heinonen, Ragnar Granit Institute, for providing the anatomical data.  ... 
doi:10.1006/cbmr.1999.1538 pmid:10860584 fatcat:zgm7ctvj2vduthar4tbqrnpbg4

Efficient computation of lead field bases and influence matrix for the FEM-based EEG and MEG inverse problem

C H Wolters, L Grasedyck, W Hackbusch
2004 Inverse Problems  
The finite element method, used for the forward problem, is able to realistically model tissue conductivity inhomogeneities and anisotropies.  ...  Our approaches can be applied to inverse reconstruction algorithms in both continuous and discrete source parameter space for EEG and MEG.  ...  center for Bioelectric Field Modeling, Simulation and Visualization.  ... 
doi:10.1088/0266-5611/20/4/007 fatcat:g5hu6xu2rbed5hj2kks3y2iup4

OpenMEEG: opensource software for quasistatic bioelectromagnetics

Alexandre Gramfort, Théodore Papadopoulo, Emmanuel Olivi, Maureen Clerc
2010 BioMedical Engineering OnLine  
A semi-realistic model often used in practise is the piecewise constant conductivity model, for which only the interfaces have to be meshed.  ...  Interpreting and controlling bioelectromagnetic phenomena require realistic physiological models and accurate numerical solvers.  ...  Acknowledgements The authors acknowledge support from the ANR grant ViMAGINE ANR-08-BLAN-0250-02, and for EO from a PhD grant from the Regional Council of Provence Alpes Cote d'Azur.  ... 
doi:10.1186/1475-925x-9-45 pmid:20819204 pmcid:PMC2949879 fatcat:dnlnzdhzijhvnequf5ldsf4hla

A New Refinement-Free Preconditioner for the Symmetric Formulation in Electroencephalography [article]

Viviana Giunzioni, John E. Ortiz G., Adrien Merlini, Simon B. Adrian, Francesco P. Andriulli
2022 arXiv   pre-print
Widely employed for the accurate solution of the electroencephalography forward problem, the symmetric formulation gives rise to a first kind, ill-conditioned operator ill-suited for complex modelling  ...  Numerical results for both canonical and realistic head models validate the effectiveness of the proposed formulation.  ...  This consideration sheds light on the paramount need for solving accurately and efficiently the forward EEG problem.  ... 
arXiv:2204.06857v1 fatcat:rfolyrgze5bj3jpb77klbyldqq

Fast Approximation of EEG Forward Problem and Application to Tissue Conductivity Estimation

Kostiantyn Maksymenko, Maureen Clerc, Theodore Papadopoulo
2019 IEEE Transactions on Medical Imaging  
To do so, the EEG forward problem solution (so-called lead field matrix) must be computed for a large number of conductivity configurations.  ...  Computing a lead field requires a matrix inversion which is computationally intensive for realistic head models.  ...  Our approach, however, is adapted for the particular structure of the EEG forward problem.  ... 
doi:10.1109/tmi.2019.2936921 pmid:31442974 fatcat:njr62q7qencjlhp5li72u3mrru
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