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Dear all,<br>
<br>
Alexandre Gramford pointed out to me that there was some discussion
ongoing on which conductivities to use for EEG-Forward-Modeling and
I'd like to move this discussion more to public for it could be
interesting for many of us. <br>
I was recently overflying some papers concerned with that very
issues and I made some interesting and discoveries, especially in <br>
<blockquote>Conductivity of living intracranial tissues. by Latikka
J, Kuurne T, Eskola H.<br>
The electrical conductivity of human cerebrospinal fluid at body
temperature by Baumann et al.<br>
</blockquote>
The first one measured the conductivities (or resistivities) of
living brain tissue and came to values of 3.51 Ohms*m and 3.91
Ohms*m for grey respectively white matter and 0.80 Ohms*m for the
CSF (which are about 0.28, 0.256 and 1.25 S/m). In contrary the
second one found a value for 1.79 S/m for CSF at body temperature
where it was about 1.4 S/m at room temperature. The Skull-To-Brain
conductivity ratio was measured for example in<br>
<blockquote>Estimation of <em>in vivo</em> brain-to-skull
conductivity ratio in humans by Yingchun Zhang, Wim van Drongelen,
and Bin He<br>
</blockquote>
where they found a ratio of about 1/18.7 which is way larger than
the commonly assumed value.<br>
<br>
I would appreciate very much if many of you could contribute to this
discussion by telling us which values you use for the conductivities
and on which publications the are based.<br>
<br>
Best,<br>
Paul<br>
<pre class="moz-signature" cols="72">--
Paul Czienskowski
Max Planck institute for human development
Lentzeallee 94
14195 Berlin
Björnsonstr. 25
12163 Berlin
Tel.: (+49)(0)30/221609359
Handy: (+49)(0)1788378772</pre>
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