A theoretical and experimental study of high resolution EEG based on surface Laplacians and cortical imaging

doi:10.1016/0013-4694(94)90112-0

Electroencephalography and Clinical Neurophysiology

Volume 90, Issue 1, January 1994, Pages 40-57

https://doi.org/10.1016/0013-4694(94)90112-0 Get rights and content

Abstract

Two different methods to improve the spatial resolution of EEG are discussed: the surface Laplacian (e.g., current source density) and cortical imaging (e.g., spatial deconvolution). The former methods tend to be independent of head volume conductor model, whereas the latter methods are more model-dependent. Computer simulations of scalp potentials due to either a few isolated sources or 4200 distributed cortical sources and studies of actual EEG data both indicate that the two methods provide similar estimates of cortical potential distribution. Typical correlation coefficients between either spline-Laplacian or cortical image and simulated (calculated) cortical potential are in the 0.8–0.95 range, depending partly on CSF thickness. By contrast, correlation coefficients between simulated scalp and cortical potential are in the 0.4–0.5 range, suggesting that high resolution methods provide much better estimates of cortical potential than is obtained with conventional EEG. The two methods are also applied to steady-state visually evoked potentials and spontaneous EEG. Correlation coefficients obtained from real EEG data are in the same general ranges as correlations obtained from simulations. The new high resolution methods can provide a dramatic increase in the information content of EEG and appear to have widespread application in both clinical and cognitive studies.

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^☆: Research at Tulane University was supported by NIH Grant R01 NS243314. Research at the Swinburne Centre for Applied Neurosciences was supported by an ARC research intrastructure grant.

¹: The authors thank Geoff Nield (in Melbourne) and Sam Law (in Seattle) for technical assistance.

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A theoretical and experimental study of high resolution EEG based on surface Laplacians and cortical imaging☆

Abstract

Electroenceph. clin. Neurophysiol.

American EEG Society Meeting, Houston 1972 and Math. Biosci.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Electroenceph. clin. Neurophysiol.

Bull. Math. Biol.

Spherical splines and the interpolation, deblurring and transformation of topographic EEG

Computed tomography and positron emission tomography correlates of cognitive decline in aging and senile dementia

Dynamic functional topography of cognitive tasks

Brain Topogr.

Analysis of multiple lead data

Beyond topographical mapping: towards functional-anatomical imaging with 124 channel EEG and 3-D MRIs

Brain Topogr.

Seeing through the skull: advanced EEGs accurately measure cortical activity from the scalp

Brain Topogr.

Numerical tests of a method for stimulating electrical potentials on the cortical surface

IEEE Trans. Biomed. Eng.

Spatial filtering to extract abnormal and artifactual components from the electroencephalogram

Interelectrode coherencies using nearest-neighbor and spherical harmonic expansion computation of Laplacian of scalp potential

Spline Generated Surface Laplacian Estimates for Improving Spatial Revolution in Electroencephalography

Ph.D. Dissertation

High resolution EEG using spline generated surface Laplacian on spherical and ellipsoidal surfaces

EEEE Trans. Biomed. Eng.

Method to reduce blur distortion from EEGs using a realistic head model

IEEE Trans. Biomed. Eng.

The cortical alpha rhythm in dog: the depth and surface profile of phase

Model of brain rhythmic activity

Kybernetik