[Eeglablist] Why most of good 'brain' ICs are 'dipolar' with show 'red'-centered scalp topos, although 2/3 of the cortex is in sulci?

[K Jeffrey Eriksen]

Here is the result of a Google Scholar search for "head conductivity and EEG". I can send you a PDF of the first paper if you like.

-Jeff Eriksen

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Google Scholar - head conductivity and EEG

Wednesday, January 10, 2024
10:21 AM

Regional head tissue conductivity estimation for improved EEG analysis
TC Ferree, KJ Eriksen… - IEEE Transactions on …, 2000 - ieeexplore.ieee.org
… is limited in the head due to the low skull conductivity [14], regional head tissue conductivity …
the head geometry is known and represent the volume with a small number of conductivity …

Simultaneous head tissue conductivity and EEG source location estimation
ZA Acar, CE Acar, S Makeig - NeuroImage, 2016 - Elsevier
… Accurate electroencephalographic (EEG) source localization requires an electrical head …
and conductivity values for the major head tissues. While consistent conductivity values have …

Influence of head tissue conductivity uncertainties on EEG dipole reconstruction
J Vorwerk, Ü Aydin, CH Wolters… - Frontiers in neuroscience, 2019 - frontiersin.org
… EEG forward solution due to head tissue conductivity uncertainties influence the results of
EEG … of the geometry and conductive features of the subject's head. Various studies have …

Determination of head conductivity frequency response in vivo with optimized EIT-EEG
J Dabek, K Kalogianni, E Rotgans, FCT van der Helm… - Neuroimage, 2016 - Elsevier
… Electroencephalography (EEG) benefits from accurate head models. Dipole source …
generic head geometry and conductivity with tailored ones. When adequate head geometry is …
Sensitivity of EEG and MEG measurements to tissue conductivity
NG Gençer, CE Acar - Physics in Medicine & Biology, 2004 - iopscience.iop.org
… the conductivity distribution of the head from EEG and/or … the head (i.e. the forward problem),
the electrical conductivity of … electrical conductivity distribution of the human head cannot yet …
The influence of tissue conductivity and head geometry on EEG measurement sensitivity distributions
K Wendel - 2010 - trepo.tuni.fi
… EEG measurement sensitivity distribution according to the influence of tissue conductivities,
electrode placement, electrode type, and geometries upon volume conductor head models…

A guideline for head volume conductor modeling in EEG and MEG
J Vorwerk, JH Cho, S Rampp, H Hamer, TR Knösche… - NeuroImage, 2014 - Elsevier
… /not modeling different conductive compartments and features of the human head—skull …
in the creation of a volume conductor on both EEG and MEG forward solutions and to compare …
Neonatal EEG at scalp is focal and implies high skull conductivity in realistic neonatal head models
M Odabaee, A Tokariev, S Layeghy, M Mesbah… - Neuroimage, 2014 - Elsevier
… We then generated realistic head models using both finite … real and simulated EEG for
different skull conductivities (from … when the selected skull conductivity for newborn was around …

Effects of uncertainty in head tissue conductivity and complexity on EEG forward modeling in neonates
H Azizollahi, A Aarabi, F Wallois - Human brain mapping, 2016 - Wiley Online Library
… in skull conductivity induced effects in the EEG forward … effect on EEG was caused by changes
in conductivity of the … impact of uncertainty in conductivity and deficiencies in head tissue …

Influence of tissue conductivity anisotropy on EEG/MEG field and return current computation in a realistic head model: a simulation and visualization study using high …
CH Wolters, A Anwander, X Tricoche, D Weinstein… - NeuroImage, 2006 - Elsevier
… head surface or from a close distance. The goal of this study was to examine the sensitivity
of the associated EEG/MEG forward problem especially to conductive … realistic head models …

Related searches
• head tissue conductivity eeg forward modeling
• eeg source analysis realistic head models
• skull conductivity head models
• head tissue conductivity magnetoencephalographic simulations
• finite element head model conductivity estimation
• conductivity ratio eeg source localization accuracy
• head geometry tissue conductivity
eeg meg anisotropic electrical conductivity

-----Original Message-----
From: eeglablist <eeglablist-bounces at sccn.ucsd.edu> On Behalf Of Scott Makeig via eeglablist
Sent: Wednesday, January 10, 2024 8:46 AM
To: Евгений Машеров <emasherov at yandex.ru>
Cc: eeglablist at sccn.ucsd.edu
Subject: Re: [Eeglablist] Why most of good 'brain' ICs are 'dipolar' with show 'red'-centerd scalp topos, although 2/3 of the cortex is in sulci?

There was an abstract presentation at a company-sponsored? session at OHBM several years ago.  I am sure Don is still interested <dmtucker at mac.com>

Scott

On Tue, Jan 9, 2024 at 12:33 AM Евгений Машеров <emasherov at yandex.ru> wrote:

> Thank you. I would like to clarify his methodology. Perhaps it is
> described in detail somewhere? It seems to me that the frequency at
> which the impedance is measured may be significant here.
>
> Eugen Masherov
>
> > Yes, this electrical stimulation approach was attempted by Don
> > Tucker's
> EGI
> > group for many years - with results that were not encouraging, the
> problem
> > being that almost all the injected current flows through the scalp,
> > whose local and time-varying conductivity also then has significant effect...
> The
> > SCALE approach treats the independent component signals compatible
> > with
> an
> > effective source in cortex (having a strongly dipolar scalp
> > projection
> with
> > equivalent dipole located in brain) as cortical stimulations, and
> > iteratively finds the (single) skull conductivity value that
> > minimizes reconstruction error of the brain sources to 'sparse,
> > compact, and smoothly' varying distribution (sometime, two
> > bilaterally near-symmetric distributions) on the imaged cortical
> > surface - using an electrical forward problem head model constructed
> > from an individual MR image - the SCS source inversion algorithm of
> > Cao Cheng. Our next step should be to build a multidimensional skull
> > conductivity map. Again, we
> are
> > attempting to put the SCALE software on NSG (
> https://urldefense.com/v3/__http://www.nsgportal.org__;!!Mih3wA!BNS_5a
> ZCEDYflkuo2qfpDZgsY0Z-xv87AU3QM1QiNdQklstxqDvGifU6oaUANNcbLSF18LJVuTtk
> Yo2KIrZI$
> ) for free
> > use.
> >
> > Scott Makeig
> >
>


--
Scott Makeig, Research Scientist and Director, Swartz Center for Computational Neuroscience, Institute for Neural Computation, University of California San Diego, La Jolla CA 92093-0559, http://sccn.ucsd.edu/~scott _______________________________________________
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