Introduction to ElectroEncephaloGraphy (EEG) and MagnetoEncephaloGraphy (MEG).
|
|
- Emily Horn
- 5 years ago
- Views:
Transcription
1 NEUR 570 Human Brain Imaging BIC Seminar 2011 Introduction to ElectroEncephaloGraphy (EEG) and MagnetoEncephaloGraphy (MEG). Christophe Grova Ph.D Biomedical Engineering Dpt Neurology and Neurosurgery Dpt Montreal Neurological Institute, McGill, University Centre de Recherches Mathématiques
2 Outline Origin of EEG and MEG signals EEG and MEG data acquisition Source localization
3 Outline Origin of EEG and MEG signals EEG and MEG data acquisition Source localization
4 A bit of history 1st EEG human recording: Dr. Hans Berger in st MEG human recording: Dr. David Cohen in 1972
5 Several brain imaging techniques Spatial scale (in mm) Epileptic spike Reference Intra-cerebral EEG recordings EEG 64 electrodes MEG 275 sensors Scalp topographies Simultaneous EEG/fMRI Hemodynamic brain response associated to EEG activity SPECT Brain perfusion FDG PET Glucose metabolism Anatomical MRI 1 ms 1 s 40 s static Temporal scale
6 Electric vs magnetic fields Moving electric charges, an electric current, create a magnetic field B
7 Electric vs magnetic signals in the brain Magneto-EncephaloGraphy (MEG): measures changes in magnetic fields on the scalp: sensitive to neuronal currents Electro-EnphaloGraphy (EEG): measures differences of electric potentials on the scalp: sensitive to conduction (volume) currents If there was air between the brain and the skull, no EEG could be measured on this subject, but it would be possible to measure MEG
8 The electro-magnetic dipole model r J p (r ) Current dipole r Measurement point Electric potential (in free space) Magnetic field (in free space)
9 Main generators or electro-magnetic scalp activity: pyramidal cells
10 Generation of a signal one can detect from scalp measurements Synchronisation of potentiels post-synaptic potentials along the cortical surface
11 Organization of pyramidal cells along the cortical surface
12 Neuronal conduction vs volume conduction Baillet et al 2001 Neuronal conduction: (primary currents) Action potentials (1ms), Post synaptic potentials (10ms) Active conduction. Origin of MEG signals Volume conduction: (secondary currents) The brain is a conductive medium Instantaneous propagation of electric fields Passive conduction. Origin of EEG signals
13 Magneto-encephalography (MEG) Measures magnetic fields generated outside the head from neuronal currents Magnetic and electric fields are perpendicular There is no influence of the skull on the propagation of magnetic fields Radial sources do not contribute to MEG signals
14 Differences between EEG and MEG Although the same neurophysiological processes generate EEG and MEG: 1. Magnetic fields are not distorted by resistance from skull and scalp better spatial resolution in MEG? 2. Electrical and magnetic fields are oriented perpendicularly to each other Hamalainen et al 1993
15 Differences between EEG and MEG cont 3. Scalp EEG is sensitive to both tangential and radial components of a current source in a sphere, while neuromagnetometers detect only its tangential components - a radial dipole does not produce a magnetic field outside the sphere David Cohen NMH/MIT
16 Differences in EEG and MEG cont - Thus, MEG selectively measures activity in the sulci. - EEG measures activity from both the gyri and the sulci (dominated by radial sources) David Cohen NMH/MIT
17 Epileptic activity: complementarity btw MEG and EEG Merlet et al 1997
18 Outline Origin of EEG and MEG signals EEG and MEG data acquisition Source localization
19 Electro-encephalography (EEG) 10/20 System (19electrodes) Measurement of scalp Electric potentials Measures potentials generated by volume conduction currents (from 19 to 256 electrodes) Scalp potentials are attenuated and distorted by the skull (highly resistive)
20 Electro-encephalography (EEG) Background Signal EEG system 19 electrodes 256 electrodes
21 EEG during wakefulness From Dr. Gotman BMDE501 lecture
22 EEG during sleep From Dr. Gotman BMDE501 lecture
23 EEG during an epileptic seizure From Dr. Gotman BMDE501 lecture
24 MEG measures magnetic fields related to brain activity from femtotesla (10-15 T) to picotesla (10-12 T) Earth s magnetic field: 4,710-5 T. small magnetic field measurements lead to artifacts MEG brain signals = hearing the noise of a pin falling on a sofa in a dance club! (M. Hamalainen)
25 Noise sources
26 Challenges in MEG data acquisition Brain magnetic fields are tiny (pt,10-12 T): MRI: 1,000,000,000,000,000 (=1T) Earth magnetic field: 100,000,000,000 Magneto-CardioGram (MCG): 100,000 MEG signals: 1,000 Sensitivity of magnetometer: 10 Highly sensitive sensors: SQUID (Superconducting QUantum Interference Device) in liquid helium (-269ºC) Noise reduction: Magnetically shielded room First order gradiometer to eliminate remote interference and record only local field Reference sensors MEG is sensitive to head motion: head localization is required MEG setup costs approximately $3M
27
28 MEG Systems CTF 275 sensors 4-D 148 or 248 sensors, NeuroMag 306 sensors KIT - Kanazawa Other (Los Alamos)
29 An highly sensitive sensor of magnetic field (ft) SQUID: Superconducting Quantum Interference Devices invented in 1965 by James Edward Zimmerman and Arnold Silver at Ford Research Lab. All the system requires superconducting state: Liquide Helium + Cryogenic Dewar
30 Environmental Noise Reduction Shielded Room Gradiometers Reference sensors used to pick up noise (3rd order gradient of env. noise)
31 Opening a MEG device Reference sensors
32 Passive noise reduction: Moving magnetic dipoles Reference system s Magnetically shielded room (mu metal) Power lines or other current lines Magnetic sensors are subjected not only to the measured MEG signal S, but also to unwanted signals (environmental noise, signals from parts of brain not being measured and other body parts).
33 Active noise cancellation: coils + external magnetometer to compensate external noise Noise cancellation coils MEG system shielded room (a) (b) Active noise cancellation. (a) coil system in an unshielded environment; (b) coil system combined with a shielded room.
34 Synthetic noise cancellation: flux transformers estimating local gradient of magnetic field 10 µt 1 µt (b) Magnetometers Power line Noise (B or G (3) d 1 d 2 d 3 ) (rms/ Hz) 100 nt 10 nt 1 nt 100 pt 10 pt 1 pt 100 ft 3rd-order gradiometer Unshielded, B Shielded, B Vibrational noise 10 ft 5 ft rms/ Hz 1 ft Frequency (Hz) Noise (G (1) d or G (3) d 1 d 2 d 3 ) (rms/ Hz) 10 µt 1 µt 100 nt 10 nt 1 nt 100 pt 10 pt 1 pt 100 ft (a) 1st-order gradiometers Shielded, G 3rd-order grad. Unshielded, G Vibrational noise Power line 10 ft 5 ft rms/ Hz 1 ft Frequency (Hz)
35 MEG is sensitive to head motions during data acquisition
36 Continuous head localization system Three emitting coils used for continuous head localization: Nasion and Peri-auricular points
37 3D localization of the three localization coils, the head shape and EEG electrodes on the subject s head Use of a magnetic device (Polhemus) for 3D localization
38 Co-registration with the subject sanatomy (skin surface segmented from anatomical MRI) MEG sensors (red) + EEG electrodes (blue) Co-registered on skin surface EEG electrodes (blue) + Digitized Head Shape (red) Co-registered on skin surface
39 Few EEG/MEG examples
40 Epileptic activity : interictal spikes Interictal spikes are spontaneous activity generated by the brain without any clinical sign Multimodal exploration is feasible Intra-cerebral EEG recordings showed that interictal spike generators are rarely focal (Merlet I. et al. Clin. Neurophys. 1999) A minimum brain activated area of 6 cm 2 is needed to generate a spike on the scalp (Ebersole J. Clin. Neurophys. 1997), spike generators may also be quite more extended than 6 cm 2 A minimum brain activated area of 3 cm 2 is needed to generate a spike on MEG EEG interictal spike
41 Epileptic spikes in EEG
42 Epileptic spikes in MEG
43 Generation of evoked activity: averaging will increase the Signal-to-Noise ratio Average of the 20 trials Trial 1 Trial 2 Trial 3.
44 Visual evoked field / potential
45 Visual evoked field / potential (left stimulation) MEG topography EEG topography Source localization
46 Somatosensory vs motor evoked field (potential) 90ms after left thumb pneumatic stimulation 20ms after left thumb tapping
47 Somatosensory vs motor evoked field (potential) 90ms after left thumb pneumatic stimulation 20ms after left thumb tapping
48 Outline Origin of EEG and MEG signals EEG and MEG data acquisition Source localization
49 Is it possible to localize source of brain activity from scalp measurements?
50 Source localization Inverse problem: estimation of sources of brain activity from EEG/MEG scalp recordings? Forward problem = modelling : knowing where are the sources, computation of the EEG/MEG signals generated by these sources?
51 Forward problem Knowing brain sources and a model of the head, one can compute corresponding electric potentials or magnetic fields generated on the scalp?
52 Spherical model: analytical solution
53 Realistic models of the head a : spherical model (analytical solution) b : realistic surface model (BEM) BrainStorm c : realistic volume model (FEM)
54 The Direct Problem is Relatively Simple We know the geometry and the electrical and magnetic properties of the brain, CSF, skull and scalp The geometry is complex: we need a mathematically manageable representation of the head. The simplest is a sphere; the more complex is a realistic head model. The electrical properties are complex: electrical conductivities cannot be measured in vivo. Bone conductivity is quite variable and is the most important factor. Magnetic properties are more homogeneous across tissues (less influence of the bone)
55 The Inverse Problem Given a distribution of electric potentials or magnetic fields at the surface of a volume conductor, where are the sources inside the volume giving rise to this distribution, and what are their characteristics?
56 Inverse problem
57 The Inverse Problem is Hopeless There is an infinite number of distribution of sources inside a volume conductor that can give rise to the same potential distribution at the surface of the conductor (Helmholtz, 1853). There is an infinite number of possible arrangement of sources inside the brain giving rise to a particular EEG or MEG signal The inverse problem is hopeless in theory. It can only be solved with simplifying assumptions = constraints
58 Selection of the more appropriate model One need to add assumptions in the model to be able to find a unique solution Are they realistic?
59 Models of the sources of brain activity Equivalent current dipole non-linear nb of sources? what is an ECD? Distributed sources anatomical constraint linear p= 10 3 sources n= 10 2 electrodes ill-conditioned pb needs regularization
60 Summary: any source localization method relies on some a priori assumptions Number of generators well-known ECD approaches Few decorrelated sources, number unknown Dipole scanning approaches Distributed network and/or extended sources Distributed sources approaches
61 Model of signal generation J Lead field (forward pb) M signal Noise
62 Model of signal generation J sources Lead field (forward pb) M signal Noise
63 Model of signal generation J sources Lead field (forward pb) M signal Noise
64 Model of signal generation J sources Lead field (forward pb) M signal Noise
65 Model of signal generation J M sources Lead field (forward pb) signal Estimate of J using and Equivalent Current Dipole Noise
66 Model of signal generation J M sources Lead field (forward pb) signal Estimate Estimate of J of constrained J using and on The Equivalent cortical surface Current Dipole Noise
67 The Equivalent Current Dipole If one assumes that the EEG or MEG signals are generated by one or a small number of dipole sources, then it is possible to solve the inverse problem. A dipole is a point source, defined by its location (3 parameters), its orientation (2 parameters) and its moment (1 parameter). Is the dipole model reasonable?
68 Estimation of the Equivalent Current Dipole G: Lead field matrix M = G(Φ).J + E Φ: dipoles location and orientation J: amplutide of the the dipole E: Noise Several types of dipole models: Moving dipole: Position?, Orientation?, Amplitude? Rotating dipole: fixed position, Orientation?, Amplitude? Fixed dipole: fixed position, fixed orientation, Amplitude? Number of dipoles: Estimation of the signal subspace (PCA) Iterative approaches Solving the inverse problem: Non-linear optimisation to find dipole locations Minimisation of residual variance:
69 Minisation of residual variance (RV) RV = M - G(Φ).J 2 / M 2 Variance non explained by the model Total variance RV is not a validation metric!!! A misleading solution can provide a very low RV
70 Is the Dipole Model Reasonable? In primary sensory evoked experiments, particularly somatosensory and auditory, the dipole model appears justified (it has been validated by comparing the results of modeling to what we know about sensory physiology). In other situations, particularly in epilepsy, the dipole model requires validation.
71
72 Can the Dipole Model be Misleading? YES In most instances, it is possible to find a dipolar source that can model well a scalp distribution. This only indicates that the dipole is a possible source of the distribution. It does not prove that it is the source of the distribution. There are systematic errors caused by the fact that the source is likely to have a significant spatial extent.
73 Confidence intervals
74
75
76 The Dipole Model: Conclusions Very powerful method to find intracerebral sources from a scalp recording. Only valid if its underlying assumptions are correct (that sources are dipolar). Appears to localize well sources of primary sensory activity. Localizes reasonably well the maximum of extended sources of epileptic activity, although secondary (small amplitude) sources are probably less reliable. No information on extent of actual source. Main limitation: number of dipoles
77 Solving the inverse problem using distributed sources M = G J + B Inverse pb: LINEAR, but ill-posed. Under-determined equation system: 10 2 measures 10 4 dipole sources (=unknown) Lead field G = ill-conditioned Regularization is needed to find a solution (requires a priori assumptions)
78 Classical assumptions Solution of minimum energy: Minimum Norm Hamalainen et al. Med Biol. Eng. Comput. 94 Solution maximum spatial smoothness: LORETA Pascual-Marqui et al. Int. J. Psychophys. 94
79 Minimum Norm Estimate
80 LORETA: maximum of spatial smoothing
81 Anatomical constraints: sources distributed on the cortical surface Dale A., Sereno M., J. Cogn. Neurosci. 5,
82 Extraction of a distributed sources model from an anatomical MRI 3D T1-weighted MRI acquisition: Matrix = 170x256x256, voxel = 1mm TR = 22 ms, TE = 9.2 ms Automatic segmentation of the cortical surface = White Matter/Grey Matter interface Brainvisa:
83 Regularization Inverse problem = ill posed problem (10,000 sources vs 100 sensors) No unique solution The problem needs regularization (assumptions) 1. Minimum norm (MN): minimum of energy (may be weighted W). Minimise M-GJ 2 + α WJ 2 2. LORETA : maximum of smoothness. Minimise J 2 under the constraint M = GJ where is a discrete spatial Laplacian operator 3. MEM : maximum entropy of the mean
84 Minimum Norm Estimate within the Bayesian Framework (1/5) Linear distributed model for source localization M: n x t signal on the n scalp sensors G: n x p forward model of Gain matrix J: p x t current density distribution on the sources along the cortical surface p >> n Bayes Law:
85 Minimum Norm Estimate within the Bayesian Framework (2/5) Bayes Law: A priori distribution of the sensor noise E: Gaussian distribution with null mean and Assumption of uncorrelated noise Data likelihood: A priori distribution of the source distribution J: Gaussian distribution with null mean and
86 Minimum Norm Estimate within the Bayesian Framework (3/5) Bayes Law: Maximum likelihood solution Data fit term Regularization hyperparameter Weighted Min. Energy constraint
87 Minimum Norm Estimate within the Bayesian Framework (4/5) Bayes Law: Maximum likelihood solution This solution depends on the regularization hyparameter α α can be estimated using the L-curve technique
88 Minimum Norm Estimate within the Bayesian Framework (5/5) Maximum likelihood solution Estimation of the regularization hyparameter α using the L-curve technique
89 Examples of source localisation of an epileptic spike using anatomical constraints fmri activation for a similar spike
90 Regularizing the ill-posed linear model: M = GJ +E 2. Maximum Entropy on the Mean (MEM) µ J (J) Reference distribution = a priori information Relative entropy MEM solution is the one with maximum µ entropy, i.e., the one that makes the least assumption regarding missing information Prior information on J: Parcelling of the cortical surface in K parcels: MEM solution p * J (J) p J (J) Data fit: set of all distributions p J (J) explaining the data on average
91 Validation Results: 4th order spatial extent (14 cm 2 ) Gold Standard: Temporo-Radial Source Gold Standard: Temporo-Tangential Source MN : AUC = 0.78 MEM : AUC = 0.93 LORETA : AUC = 0.99 MN : AUC = 0.79 MEM : AUC = 0.93 LORETA : AUC = 0.96 Grova C, Daunizeau J, Lina JM, Benar CG, Benali H, Gotman J. Neuroimage Feb 1;29(3):
92 Validation Results: MEG source localization (1/2) Chowdhury R. et al, Proc. of HBM 2010 conference
93 Application of model evidence for model comparison: Henson et al. Neuroimage 2009
94 Validation: comparison between MEM source localization and intracranial EEG recordings Lina et al, IEEE TBME Sumitted
95 Summary: any source localization method relies on some a priori assumptions Number of generators well-known ECD approaches Few decorrelated sources, number unknown Dipole scanning approaches Distributed network and/or extended sources Distributed sources approaches Requires a good knowledge of the signal to be localized Requires statistics (SPM-like, non parametric) Requires the comparaison of several methods
96 Take home messages Complementarity between EEG and MEG: MEG signals are not distorted by the skull (better spatial accuracy) MEG can see only tangential sources whereas EEG can see tangential and radial sources MEG data acquisition is challenging: tiny magnetic fields in a noisy environment EEG/MEG source localization: Any source localization requires an a priori model of the underlying sources Main models: Equivalent current dipole Dipole scanning approaches Distributed sources (along the cortical surface) Model comparison or model selection is required (hypothesis test) Multimodal data fusion: There is no one to one correspondance between EEG source, MEG source and BOLD response: COMPLEMENTARITY EEG/MEG sources can be associated either with BOLD activation or deactivation EEG/MEG signals require synchronization of neuronal activity, the BOLD signal does not
97 Suggested Bibliography Niedermeyer s ElectroEncephalography: Basic Principles, Clinical Applications and Related Fields. 6 th Edition, Ed. D.L. Schomer and F.H. Lopes da Silva. Wolters Kuwer, Lippincott Williams and Wilkins MEG: an introduction to methods. Eds. P.C. Hansen, M.L. Kringelbach and R.Salmelin Oxford University Press Review Papers Baillet S., Mosher J., Leahy R., Electromagnetic brain mapping. IEEE Signal Process. Mag., Hamalainen, M, Hari, R, Ilmoniemi, R, Knuutila, J, Lounasmaa, O (1993). Magnetoencephalography--theory, instrumentation, and applications to noninvasive studies of the working human brain. Rev Mod Phys, 65: Michel C., Murray M., Lantz G., Gonzales S., Spinelli L., Grave de Peralta R., EEG source imaging. Clin. Neurophysiol. 115,
98 MEG The Neuro 275 magnetometers (MEG sensors) 64 simultaneous EEG all channels up to 12kHz multimodal stimulus presentation (video, audio, somesthetic,...) audio, video subject monitoring operates in upright or supine positions located in the Neuro s new extension
99 The Neuro: more information
100 NEW COURSE offered in January 2012: BMDE 610 Functional Neuroimaging fusion Registration is now open on Minerva for Winter 2012 Space is limited, register ASAP!!!
101 Acknowledgements The Multimodal Functional Imaging Lab. (Multi-FunkIm) Christophe Grova R. Chowdhury, Y. Potiez, A. Machado, T. Hedrich, A. Blanc Montreal Neurological Inst. Eliane Kobayashi M.L. Jones, M. Aiguabella M. Sangani, D. Rosenberg, M. Porras-Betancourt Ecole de Technologie Sup. Jean Marc Lina A.S. Dubarry E. Lemay S. Deslauriers Collaborators: -MNI EEG/fMRI studies: J. Gotman, F. Dubeau, an their team!
M/EEG source analysis
Jérémie Mattout Lyon Neuroscience Research Center Will it ever happen that mathematicians will know enough about the physiology of the brain, and neurophysiologists enough of mathematical discovery, for
More informationMEG Source Localization Using an MLP With Distributed Output Representation
MEG Source Localization Using an MLP With Distributed Output Representation Sung Chan Jun, Barak A. Pearlmutter, Guido Nolte CBLL Meeting October 5, 2005 Source localization Definition: Identification
More informationEEG/MEG Inverse Solution Driven by fmri
EEG/MEG Inverse Solution Driven by fmri Yaroslav Halchenko CS @ NJIT 1 Functional Brain Imaging EEG ElectroEncephaloGram MEG MagnetoEncephaloGram fmri Functional Magnetic Resonance Imaging others 2 Functional
More informationNeural mass model parameter identification for MEG/EEG
Neural mass model parameter identification for MEG/EEG Jan Kybic a, Olivier Faugeras b, Maureen Clerc b, Théo Papadopoulo b a Center for Machine Perception, Faculty of Electrical Engineering, Czech Technical
More informationEstimation de paramètres électrophysiologiques pour
Introduction Estimation de paramètres électrophysiologiques pour l imagerie cérébrale Maureen Clerc Inria Sophia Antipolis, France Paris, 20 jan 2017 Séminaire Jacques-Louis Lions Maureen Clerc (Inria,
More informationIn: W. von der Linden, V. Dose, R. Fischer and R. Preuss (eds.), Maximum Entropy and Bayesian Methods, Munich 1998, Dordrecht. Kluwer, pp
In: W. von der Linden, V. Dose, R. Fischer and R. Preuss (eds.), Maximum Entropy and Bayesian Methods, Munich 1998, Dordrecht. Kluwer, pp. 17-6. CONVERGENT BAYESIAN FORMULATIONS OF BLIND SOURCE SEPARATION
More informationElectromagnetic inverse problems in biomedical engineering Jens Haueisen
Electromagnetic inverse problems in biomedical engineering Jens Haueisen Institute of Biomedical Engineering and Informatics Technical University of Ilmenau Germany Biomagnetic Center Department of Neurology
More informationTransformation of Whole-Head MEG Recordings Between Different Sensor Positions
Transformation of Whole-Head MEG Recordings Between Different Sensor Positions Transformation von Ganzkopf-MEG-Messungen zwischen verschiedenen Sensorpositionen Thomas R. Knösche Max Planck Institute of
More informationSENSITIVITY COMPUTATIONS FOR ELLIPTIC EQUATIONS WITH INTERFACES. Virginia Polytechnic Institute and State University Blacksburg, VA,
SENSITIVITY COMPUTATIONS FOR ELLIPTIC EQUATIONS WITH INTERFACES J.A. Burns 1, D. Rubio 2 and M. I. Troparevsky 3 1 Interdisciplinary Center for Applied Mathematics Virginia Polytechnic Institute and State
More informationContents. Introduction The General Linear Model. General Linear Linear Model Model. The General Linear Model, Part I. «Take home» message
DISCOS SPM course, CRC, Liège, 2009 Contents The General Linear Model, Part I Introduction The General Linear Model Data & model Design matrix Parameter estimates & interpretation Simple contrast «Take
More informationFORSCHUNGSZENTRUM JÜLICH GmbH Zentralinstitut für Angewandte Mathematik D Jülich, Tel. (02461)
FORSCHUNGSZENTRUM JÜLICH GmbH Zentralinstitut für Angewandte Mathematik D-52425 Jülich, Tel. (2461) 61-642 Interner Bericht Temporal and Spatial Prewhitening of Multi-Channel MEG Data Roland Beucker, Heidi
More informationEEG/MEG Error Bounds for a Static Dipole Source with a Realistic Head Model
470 IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 49, NO. 3, MARCH 2001 EEG/MEG Error Bounds for a Static Dipole Source with a Realistic Head Model Carlos H. Muravchik, Senior Member, IEEE, and Arye Nehorai,
More informationLocalization of Multiple Deep Epileptic Sources in a Realistic Head Model via Independent Component Analysis
Localization of Multiple Deep Epileptic Sources in a Realistic Head Model via Independent Component Analysis David Weinstein, Leonid Zhukov, Geoffrey Potts Email: dmw@cs.utah.edu, zhukov@cs.utah.edu, gpotts@rice.edu
More informationDevelopment of High-resolution EEG Devices
IJBEM 999, (), - www.tut.fi/ijbem/ Development of High-resolution EEG Devices Thomas C. Ferree a,b and Don M. Tucker a,b a Electrical Geodesics, Inc., Riverfront Research Park, Eugene, OR 973 b Department
More informationBasic MRI physics and Functional MRI
Basic MRI physics and Functional MRI Gregory R. Lee, Ph.D Assistant Professor, Department of Radiology June 24, 2013 Pediatric Neuroimaging Research Consortium Objectives Neuroimaging Overview MR Physics
More informationConfidence Interval of Single Dipole Locations Based on EEG Data
Brain Topography, Volume 10, Number 1,1997 31 Confidence Interval of Single Dipole Locations Based on EEG Data Christoph Braun*, Stefan Kaiser*, WilhelmEmil Kineses*, and Thomas Elbert^ Summary: Noise
More informationModeling of post-surgical brain and skull defects in the EEG inverse problem with the boundary element method
Clinical Neurophysiology 113 (2002) 48 56 www.elsevier.com/locate/clinph Modeling of post-surgical brain and skull defects in the EEG inverse problem with the boundary element method C.G. Bénar, J. Gotman*
More informationSpatial Source Filtering. Outline EEG/ERP. ERPs) Event-related Potentials (ERPs( EEG
Integration of /MEG/fMRI Vince D. Calhoun, Ph.D. Director, Image Analysis & MR Research The MIND Institute Outline fmri/ data Three Approaches to integration/fusion Prediction Constraints 2 nd Level Fusion
More informationAN ITERATIVE DISTRIBUTED SOURCE METHOD FOR THE DIVERGENCE OF SOURCE CURRENT IN EEG INVERSE PROBLEM
J. KSIAM Vol.12, No.3, 191 199, 2008 AN ITERATIVE DISTRIBUTED SOURCE METHOD FOR THE DIVERGENCE OF SOURCE CURRENT IN EEG INVERSE PROBLEM JONGHO CHOI 1, CHNAG-OCK LEE 2, AND HYUN-KYO JUNG 1 1 SCHOOL OF ELECTRICAL
More information2015 U N I V E R S I T I T E K N O L O G I P E T R O N A S
Multi-Modality based Diagnosis: A way forward by Hafeez Ullah Amin Centre for Intelligent Signal and Imaging Research (CISIR) Department of Electrical & Electronic Engineering 2015 U N I V E R S I T I
More informationStandardized low resolution brain electromagnetic tomography (sloreta): technical details
Standardized low resolution brain electromagnetic tomography (sloreta): technical details R.D. Pascual-Marqui The KEY Institute for Brain-Mind Research, University Hospital of Psychiatry Lenggstr. 31,
More informationVoltage Maps. Nearest Neighbor. Alternative. di: distance to electrode i N: number of neighbor electrodes Vi: voltage at electrode i
Speech 2 EEG Research Voltage Maps Nearest Neighbor di: distance to electrode i N: number of neighbor electrodes Vi: voltage at electrode i Alternative Spline interpolation Current Source Density 2 nd
More informationSpatial Filter Approach for Evaluation of the Surface Laplacian of the Electroencephalogram and Magnetoencephalogram
Annals of Biomedical Engineering, Vol. 29, pp. 202 213, 2001 Printed in the USA. All rights reserved. 0090-6964/2001/29 3 /202/12/$15.00 Copyright 2001 Biomedical Engineering Society Spatial Filter Approach
More informationBeamforming Techniques Applied in EEG Source Analysis
Beamforming Techniques Applied in EEG Source Analysis G. Van Hoey 1,, R. Van de Walle 1, B. Vanrumste 1,, M. D Havé,I.Lemahieu 1 and P. Boon 1 Department of Electronics and Information Systems, University
More informationNew Machine Learning Methods for Neuroimaging
New Machine Learning Methods for Neuroimaging Gatsby Computational Neuroscience Unit University College London, UK Dept of Computer Science University of Helsinki, Finland Outline Resting-state networks
More informationThe Physics in Psychology. Jonathan Flynn
The Physics in Psychology Jonathan Flynn Wilhelm Wundt August 16, 1832 - August 31, 1920 Freud & Jung 6 May 1856 23 September 26 July 1875 6 June Behaviorism September 14, 1849 February 27, 1936 August
More informationCausal modeling of fmri: temporal precedence and spatial exploration
Causal modeling of fmri: temporal precedence and spatial exploration Alard Roebroeck Maastricht Brain Imaging Center (MBIC) Faculty of Psychology & Neuroscience Maastricht University Intro: What is Brain
More informationA study of dipole localization accuracy for MEG and EEG using a human skull phantom
A study of dipole localization accuracy for MEG and EEG using a human skull phantom R. M. Leahy +, J. C. Mosher *, M. E. Spencer ++, M. X. Huang **, and J. D. Lewine *** + Signal & Image Processing Institute,
More informationwissen leben WWU Münster
MÜNSTER Sparsity Constraints in Bayesian Inversion Inverse Days conference in Jyväskylä, Finland. Felix Lucka 19.12.2012 MÜNSTER 2 /41 Sparsity Constraints in Inverse Problems Current trend in high dimensional
More informationEEG- Signal Processing
Fatemeh Hadaeghi EEG- Signal Processing Lecture Notes for BSP, Chapter 5 Master Program Data Engineering 1 5 Introduction The complex patterns of neural activity, both in presence and absence of external
More informationBayesian analysis of the neuromagnetic inverse
Bayesian analysis of the neuromagnetic inverse problem with l p -norm priors Toni Auranen, a, Aapo Nummenmaa, a Matti S. Hämäläinen, b Iiro P. Jääskeläinen, a,b Jouko Lampinen, a Aki Vehtari, a and Mikko
More informationFirst Technical Course, European Centre for Soft Computing, Mieres, Spain. 4th July 2011
First Technical Course, European Centre for Soft Computing, Mieres, Spain. 4th July 2011 Linear Given probabilities p(a), p(b), and the joint probability p(a, B), we can write the conditional probabilities
More informationEstimating Evoked Dipole Responses in Unknown Spatially Correlated Noise with EEG/MEG Arrays
IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 48, NO. 1, JANUARY 2000 13 Estimating Evoked Dipole Responses in Unknown Spatially Correlated Noise with EEG/MEG Arrays Aleksar Dogžić, Student Member, IEEE,
More informationA Performance Study of various Brain Source Imaging Approaches
A Performance Study of various Brain Source Imaging Approaches Hanna Becker, Laurent Albera, Pierre Comon, Rémi Gribonval, Fabrice Wendling, Isabelle Merlet To cite this version: Hanna Becker, Laurent
More informationPart 2: Multivariate fmri analysis using a sparsifying spatio-temporal prior
Chalmers Machine Learning Summer School Approximate message passing and biomedicine Part 2: Multivariate fmri analysis using a sparsifying spatio-temporal prior Tom Heskes joint work with Marcel van Gerven
More informationSuperconducting QUantum Interference Device (SQUID) and applications. Massoud Akhtari PhD
Superconducting QUantum Interference Device (SQUID) and applications Massoud Akhtari PhD Topics Superconductivity Definitions SQUID Principles Applications Superconductivity Conduction lattice has zero
More informationFEMMethodfortheEEGForwardProblemandImprovement Based on Modification of the Saint Venant s Method
Progress In Electromagnetics Research, Vol. 153, 11 22, 2015 FEMMethodfortheEEGForwardProblemandImprovement Based on Modification of the Saint Venant s Method Takfarinas Medani 1, *,DavidLautru 2,DenisSchwartz
More informationEffective Connectivity & Dynamic Causal Modelling
Effective Connectivity & Dynamic Causal Modelling Hanneke den Ouden Donders Centre for Cognitive Neuroimaging Radboud University Nijmegen Advanced SPM course Zurich, Februari 13-14, 2014 Functional Specialisation
More informationDynamic Causal Modelling for EEG/MEG: principles J. Daunizeau
Dynamic Causal Modelling for EEG/MEG: principles J. Daunizeau Motivation, Brain and Behaviour group, ICM, Paris, France Overview 1 DCM: introduction 2 Dynamical systems theory 3 Neural states dynamics
More informationComputational Modeling of Human Head Electromagnetics for Source Localization of Milliscale Brain Dynamics
Computational Modeling of Human Head Electromagnetics for Source Localization of Milliscale Brain Dynamics Allen D. MALONY a,1, Adnan SALMAN b, Sergei TUROVETS c, Don TUCKER c, Vasily VOLKOV d, Kai LI
More informationTHE RECIPROCAL APPROACH TO THE INVERSE PROBLEM OF ELECTROENCEPHALOGRAPHY
THE RECIPROCAL APPROACH TO THE INVERSE PROBLEM OF ELECTROENCEPHALOGRAPHY Stefan Finke, Ramesh M. Gulrajani, Jean Gotman 2 Institute of Biomedical Engineering, Université de Montréal, Montréal, Québec,
More informationApproximating Dipoles from Human EEG Activity: The Effect of Dipole Source Configuration on Dipolarity Using Single Dipole Models
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 46, NO. 2, FEBRUARY 1999 125 Approximating Dipoles from Human EEG Activity: The Effect of Dipole Source Configuration on Dipolarity Using Single Dipole
More informationFinal Report For Undergraduate Research Opportunities Project Name: Biomedical Signal Processing in EEG. Zhang Chuoyao 1 and Xu Jianxin 2
ABSTRACT Final Report For Undergraduate Research Opportunities Project Name: Biomedical Signal Processing in EEG Zhang Chuoyao 1 and Xu Jianxin 2 Department of Electrical and Computer Engineering, National
More informationMagnetoencephalographic (MEG) Characterization of Dynamic Brain Activation
11.07.2004 Hämäläinen and Hari version 2.4 page 1 Magnetoencephalographic (MEG) Characterization of Dynamic Brain Activation Basic Principles and Methods of Data Collection and Source Analysis Matti Hämäläinen
More informationDynamic Causal Modelling for EEG and MEG. Stefan Kiebel
Dynamic Causal Modelling for EEG and MEG Stefan Kiebel Overview 1 M/EEG analysis 2 Dynamic Causal Modelling Motivation 3 Dynamic Causal Modelling Generative model 4 Bayesian inference 5 Applications Overview
More informationRealtime MEG source localization with realistic noise
Realtime MEG source localization with realistic noise Sung Chan Jun Barak A. Pearlmutter Guido Nolte Department of Computer Science University of New Mexico Albuquerque, NM 87 junsc,bap,nolte @cs.unm.edu
More informationBasic concepts of MEG and EEG
Basic concepts of MEG and EEG Andreas A. Ioannides Lab. for Human Brain Dynamics, AAI Scientific Cultural Services Ltd., Nicosia, Cyprus Introductory notes for course: Foundation Themes for Advanced EEG/MEG
More informationIEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 52, NO. 3, MARCH
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 52, NO. 3, MARCH 2005 471 Distinguishing Between Moving and Stationary Sources Using EEG/MEG Measurements With an Application to Epilepsy İmam Şamil Yetik*,
More informationIEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 56, NO. 3, MARCH /$ IEEE
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 56, NO. 3, MARCH 2009 587 Effect of Head Shape Variations Among Individuals on the EEG/MEG Forward and Inverse Problems Nicolás von Ellenrieder, Member,
More informationA Rao-Blackwellized particle filter for magnetoencephalography
A Rao-Blackwellized particle filter for magnetoencephalography C Campi Dipartimento di Matematica, Università di Genova, via Dodecaneso 35, 16146 Genova, Italy A Pascarella Dipartimento di Matematica,
More informationElectroencephalography: new sensor techniques and analysis methods
Electroencephalography: new sensor techniques and analysis methods Jens Ilmenau University of Technology, Ilmenau, Germany Introduction BACKGROUND Reconstruction of electric current sources in the brain
More informationEL-GY 6813/BE-GY 6203 Medical Imaging, Fall 2016 Final Exam
EL-GY 6813/BE-GY 6203 Medical Imaging, Fall 2016 Final Exam (closed book, 1 sheets of notes double sided allowed, no calculator or other electronic devices allowed) 1. Ultrasound Physics (15 pt) A) (9
More informationModelling temporal structure (in noise and signal)
Modelling temporal structure (in noise and signal) Mark Woolrich, Christian Beckmann*, Salima Makni & Steve Smith FMRIB, Oxford *Imperial/FMRIB temporal noise: modelling temporal autocorrelation temporal
More informationDetermination of measurement noise, conductivity errors and electrode mislocalization effects to somatosensory dipole localization.
Biomed Res- India 2012; 23 (4): 581-588 ISSN 0970-938X Scientific Publishers of India Determination of measurement noise, conductivity errors and electrode mislocalization effects to somatosensory dipole
More information腦電磁波於腦功能造影之應用. Outline. Introduction. Introduction. Functional Imaging of Brain Activity. Major References
Major References Hämäläinen, M. et al. Magneto-encephalo-graphy theory, instrumentation, and applications to non-invasive studies of the working human brain. Review of Modern Physics. 1993; 65(2):413-497.
More informationPaired MEG Data Set Source Localization Using Recursively Applied and Projected (RAP) MUSIC
1248 IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 47, NO. 9, SEPTEMBER 2000 Paired MEG Data Set Source Localization Using Recursively Applied and Projected (RAP) MUSIC John J. Ermer, Member, IEEE,
More informationMEG and fmri for nonlinear estimation of neural activity
Copyright 2009 SS&C. Published in the Proceedings of the Asilomar Conference on Signals, Systems, and Computers, November 1-4, 2009, Pacific Grove, California, USA MEG and fmri for nonlinear estimation
More informationRecipes for the Linear Analysis of EEG and applications
Recipes for the Linear Analysis of EEG and applications Paul Sajda Department of Biomedical Engineering Columbia University Can we read the brain non-invasively and in real-time? decoder 1001110 if YES
More informationTHE electroencephalogram (EEG) provides neuroscientists
1358 IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 51, NO. 8, AUGUST 2004 Quantitative Approximation of the Cortical Surface Potential From EEG and ECoG Measurements Mark A. Kramer and Andrew J. Szeri*
More informationAdaptive Signal Complexity Analysis of Epileptic MEG
Adaptive Signal Complexity Analysis of Epileptic MEG ADAM V. ADAMOPOULOS Medical Physics Laboratory, Department of Medicine Democritus University of Thrace GR-68 00, Alexandroupolis HELLAS Abstract: -
More informationUsing ParExPDE for the numerical solution of bioelectric field problems
Using ParExPDE for the numerical solution of bioelectric field problems Christoph Freundl Friedrich-Alexander-Universität Erlangen-Nürnberg Christoph.Freundl@informatik.uni-erlangen.de Harald Köstler Friedrich-Alexander-Universität
More informationIEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 55, NO. 3, MARCH
IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 55, NO. 3, MARCH 2008 1103 Array Response Kernels for EEG and MEG in Multilayer Ellipsoidal Geometry David Gutiérrez*, Member, IEEE, and Arye Nehorai,
More informationCONDUCTIVITY ESTIMATION WITH EEG/MEG BRAIN SOURCE LOCALIZATION IN A FINITE ELEMENT HEAD MODEL
CONDUCTIVITY ESTIMATION WITH EEG/MEG BRAIN SOURCE LOCALIZATION IN A FINITE ELEMENT HEAD MODEL by Seok Lew A dissertation submitted to the faculty of The University of Utah in partial fulfillment of the
More informationHEAD MOTION EVALUATION AND CORRECTION IN MAGNETOENCEPHALOGRAPHY INNA V. MCGOWIN. A Dissertation Submitted to the Graduate Faculty of
HEAD MOTION EVALUATION AND CORRECTION IN MAGNETOENCEPHALOGRAPHY BY INNA V. MCGOWIN A Dissertation Submitted to the Graduate Faculty of WAKE FOREST UNIVERSITY GRADUATE SCHOOL OF ARTS AND SCIENCES in Partial
More informationC H A P T E R 4 Bivariable and Multivariable Analysis of EEG Signals
C H A P T E R 4 Bivariable and Multivariable Analysis of EEG Signals Rodrigo Quian Quiroga The chapters thus far have described quantitative tools that can be used to extract information from single EEG
More informationIndependent Component Analysis for identification of artifacts in Magnetoencephalographic recordings
Independent Component Analysis for identification of artifacts in Magnetoencephalographic recordings Ricardo Vigario 1 ; Veikko J ousmiiki2, Matti Hiimiiliiinen2, Riitta Hari2, and Erkki Oja 1 1 Lab. of
More informationStatistical inference for MEG
Statistical inference for MEG Vladimir Litvak Wellcome Trust Centre for Neuroimaging University College London, UK MEG-UK 2014 educational day Talk aims Show main ideas of common methods Explain some of
More informationDesigning Polymer Thick Film Intracranial Electrodes for Use in Intra-Operative MRI Setting.
Excerpt from the Proceedings of the COMSOL Conference 29 Boston Designing Polymer Thick Film Intracranial Electrodes for Use in Intra-Operative MRI Setting. G. Bonmassar 1 * and A. Golby 2 1 AA. Martinos
More informationAPP01 INDEPENDENT COMPONENT ANALYSIS FOR EEG SOURCE LOCALIZATION IN REALISTIC HEAD MODELS. Proceedings of 3ICIPE
Proceedings of 3ICIPE Inverse Problems in Engineering: Theory and Practice 3rd Int. Conference on Inverse Problems in Engineering June 3-8, 999, Port Ludlow, Washington, USA APP INDEPENDENT COMPONENT ANALYSIS
More informationRecent advances in the analysis of biomagnetic signals
Recent advances in the analysis of biomagnetic signals Kensuke Sekihara Mind Articulation Project, Japan Science and echnology Corporation okyo Metropolitan Institute of echnology Application of spatial
More informationDynamic Modeling of Brain Activity
0a Dynamic Modeling of Brain Activity EIN IIN PC Thomas R. Knösche, Leipzig Generative Models for M/EEG 4a Generative Models for M/EEG states x (e.g. dipole strengths) parameters parameters (source positions,
More informationThe General Linear Model (GLM)
he General Linear Model (GLM) Klaas Enno Stephan ranslational Neuromodeling Unit (NU) Institute for Biomedical Engineering University of Zurich & EH Zurich Wellcome rust Centre for Neuroimaging Institute
More informationPARTICLE FILTERING, BEAMFORMING AND MULTIPLE SIGNAL CLASSIFICATION FOR THE ANALYSIS OF MAGNETOENCEPHALOGRAPHY TIME SERIES: A COMPARISON OF ALGORITHMS
Volume X, No. X, X, X XX Web site: http://www.aimsciences.org PARTICLE FILTERING, BEAMFORMING AND MULTIPLE SIGNAL CLASSIFICATION FOR THE ANALYSIS OF MAGNETOENCEPHALOGRAPHY TIME SERIES: A COMPARISON OF
More informationMethods to Improve the Spatial Resolution of EEG
IJBEM 1999, 1(1), 10-111 www.tut.fi/ijbem/ Methods to Improve the Spatial Resolution of EEG Ramesh Srinivasan The Neurosciences Institute, 10640 John Jay Hopkins Drive, San Diego, USA Abstract Theoretical
More informationWill Penny. 21st April The Macroscopic Brain. Will Penny. Cortical Unit. Spectral Responses. Macroscopic Models. Steady-State Responses
The The 21st April 2011 Jansen and Rit (1995), building on the work of Lopes Da Sliva and others, developed a biologically inspired model of EEG activity. It was originally developed to explain alpha activity
More informationDynamic Causal Modelling for EEG and MEG
Dynamic Causal Modelling for EEG and MEG Stefan Kiebel Ma Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany Overview 1 M/EEG analysis 2 Dynamic Causal Modelling Motivation 3 Dynamic
More information840 IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 53, NO. 5, MAY 2006
840 IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 53, NO. 5, MAY 2006 Performance Analysis of Reduced-Rank Beamformers for Estimating Dipole Source Signals Using EEG/MEG David Gutiérrez, Member, IEEE,
More informationNormalized Cumulative Periodogram Method For Tuning A Regularization Parameter of The EEG Inverse Problem
Normalized Cumulative Periodogram Method For Tuning A Regularization Parameter of The EEG Inverse Problem Mohammed J. Aburidi * Adnan Salman Computer Science Department, An-Najah National University, P.O.
More informationIndependent component analysis applied to biophysical time series and EEG. Arnaud Delorme CERCO, CNRS, France & SCCN, UCSD, La Jolla, USA
Independent component analysis applied to biophysical time series and EEG Arnad Delorme CERCO, CNRS, France & SCCN, UCSD, La Jolla, USA Independent component analysis Cocktail Party Mixtre of Brain sorce
More informationNumerical Aspects of Spatio-Temporal Current Density Reconstruction from EEG-/MEG-Data
314 IEEE TRANSACTIONS ON MEDICAL IMAGING, VOL 20, NO 4, APRIL 2001 Numerical Aspects of Spatio-Temporal Current Density Reconstruction from EEG-/MEG-Data Uwe Schmitt, Alfred K Louis*, Felix Darvas, Helmut
More informationNeuromagnetic source localization using anatomical information and advanced computational methods Satu Tissari. Finnish IT center for science
CSC Research Reports R02/03 Neuromagnetic source localization using anatomical information and advanced computational methods Satu Tissari Finnish IT center for science Department of Engineering Physics
More informationOutline. Superconducting magnet. Magnetic properties of blood. Physiology BOLD-MRI signal. Magnetic properties of blood
Magnetic properties of blood Physiology BOLD-MRI signal Aart Nederveen Department of Radiology AMC a.j.nederveen@amc.nl Outline Magnetic properties of blood Moses Blood oxygenation BOLD fmri Superconducting
More informationSpatial Harmonic Analysis of EEG Data
Spatial Harmonic Analysis of EEG Data Uwe Graichen Institute of Biomedical Engineering and Informatics Ilmenau University of Technology Singapore, 8/11/2012 Outline 1 Motivation 2 Introduction 3 Material
More informationMeasures to reduce the residual field and field gradient inside a magnetically shielded room by a factor of more than 10
Metrol. Meas. Syst., Vol. XX (2013), No. 2, pp. 239 248. METROLOGY AND MEASUREMENT SYSTEMS Index 330930, ISSN 0860-8229 www.metrology.pg.gda.pl Measures to reduce the residual field and field gradient
More informationFunctional brain imaging: extracting temporal responses of multiple cortical areas from multi-focal visual evoked potentials. Shahram Dastmalchi
Functional brain imaging: extracting temporal responses of multiple cortical areas from multi-focal visual evoked potentials. By Shahram Dastmalchi B.S. (University of California, Davis) 99 A dissertation
More informationAdaptive Spatial Filters with predefined Region of Interest for EEG based Brain-Computer-Interfaces
Adaptive Spatial Filters with predefined Region of Interest for EEG based Brain-Computer-Interfaces Moritz Grosse-Wentrup Institute of Automatic Control Engineering Technische Universität München 80333
More informationA spatiotemporal dynamic distributed solution to the MEG inverse problem
A spatiotemporal dynamic distributed solution to the MEG inverse problem The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation
More informationEstimating Neural Sources from Each Time-Frequency Component of Magnetoencephalographic Data
642 IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 47, NO. 5, MAY 2000 Estimating Neural Sources from Each Time-Frequency Component of Magnetoencephalographic Data Kensuke Sekihara*, Member, IEEE, Srikantan
More informationImagent for fnirs and EROS measurements
TECHNICAL NOTE Imagent for fnirs and EROS measurements 1. Brain imaging using Infrared Photons Brain imaging techniques can be broadly classified in two groups. One group includes the techniques that have
More informationFrom Last Time. Partially full bands = metal Bands completely full or empty = insulator / seminconductor
From Last Time Solids are large numbers of atoms arranged in a regular crystal structure. Each atom has electron quantum states, but interactions shift the energies. End result is each type atomic electron
More informationEEG SOURCE RECONSTRUCTION PERFORMANCE AS A FUNCTION OF SKULL CONDUCTANCE CONTRAST. Sofie Therese Hansen, Lars Kai Hansen
EEG SOURCE RECONSTRUCTION PERFORMANCE AS A FUNCTION OF SKULL CONDUCTANCE CONTRAST Sofie Therese Hansen, Lars Kai Hansen Technical University of Denmark; Department of Applied Mathematics and Computer Science;
More informationAnatomically constrained minimum variance beamforming applied to EEG
Exp Brain Res (2011) 214:515 528 DOI 10.1007/s00221-011-2850-5 RESEARCH ARTICLE Anatomically constrained minimum variance beamforming applied to EEG Vyacheslav Murzin Armin Fuchs J. A. Scott Kelso Received:
More informationIntroduction to EEG/MEG and the FieldTrip toolbox. Robert Oostenveld
Introduction to EEG/MEG and the FieldTrip toolbox Robert Oostenveld Donders Institute for Brain, Cognition and Behaviour Radboud University Nijmegen, The Netherlands What is FieldTrip a MATLAB toolbox
More informationCitation IEEE Transactions on Magnetics (201.
Effect of Spatial Homogeneity of Sp TitleMagnetic Field Response of an Optic Magnetometer Using a Hybrid Cell of Author(s) Ito, Yosuke; Ohnishi, Hiroyuki; Kam Tetsuo Citation IEEE Transactions on Magnetics
More informationThe General Linear Model. Guillaume Flandin Wellcome Trust Centre for Neuroimaging University College London
The General Linear Model Guillaume Flandin Wellcome Trust Centre for Neuroimaging University College London SPM Course Lausanne, April 2012 Image time-series Spatial filter Design matrix Statistical Parametric
More informationPrediction of Synchrostate Transitions in EEG Signals Using Markov Chain Models
1 Prediction of Synchrostate Transitions in EEG Signals Using Markov Chain Models Wasifa Jamal, Saptarshi Das, Ioana-Anastasia Oprescu, and Koushik Maharatna, Member, IEEE Abstract This paper proposes
More informationARTEFACT DETECTION IN ASTROPHYSICAL IMAGE DATA USING INDEPENDENT COMPONENT ANALYSIS. Maria Funaro, Erkki Oja, and Harri Valpola
ARTEFACT DETECTION IN ASTROPHYSICAL IMAGE DATA USING INDEPENDENT COMPONENT ANALYSIS Maria Funaro, Erkki Oja, and Harri Valpola Neural Networks Research Centre, Helsinki University of Technology P.O.Box
More informationImaging Brain Structure and Function
Imaging Brain Structure and Function Thomas J. Grabowski, Jr., MD Professor, Radiology and Neurology (joint) Director, UW Integrated Brain Imaging Center Director, UW Alzheimer s Disease Research Center
More informationTHE PROBLEM of localizing the sources of event related. Recursive MUSIC: A Framework for EEG and MEG Source Localization
1342 IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 45, NO. 11, NOVEMBER 1998 Recursive MUSIC: A Framework for EEG and MEG Source Localization John C. Mosher,* Member, IEEE, and Richard M. Leahy, Member,
More informationDiamond Sensors for Brain Imaging
Revolutions in Biotechnology Diamond Sensors for Brain Imaging This material is based upon work supported by the Assistant Secretary of Defense for Research and Engineering under Air Force ontract No.
More information