Dear Gregor,
you might also what to use OpenMEEG [1] which supports an arbitrary number of
nested layers. It might however be tricky to produce good meshes with just a T1
and it would certainly require a recent desktop computer with a few CPUs.
Best regards,
Alex
[1] http://openmeeg.gforge.inria.fr
On Fri, Jan 20, 2012 at 9:10 PM, Vladimir Litvak
<[log in to unmask]> wrote:
> Yes, brain and CSF is the same thing for this particular purpose. You can
> get more technical details from Christophe (CCed) who wrote the BEM code.
>
> Best,
>
> Vladimir
>
>
> On Fri, Jan 20, 2012 at 6:31 PM, Gregor Strobbe <[log in to unmask]>
> wrote:
>>
>> Thank you for your answer,
>>
>> I assume the CSF isn't modeled, just one brain compartment with one
>> conductivity value?
>>
>> I am asking this, because I want to build exactly the same model based on
>> the Finite Difference Method to compare with BEM as a first comparison step.
>> The next step is to compare with more advanced FDM head models.
>>
>> Kind regards
>>
>>
>> 2012/1/20 Vladimir Litvak <[log in to unmask]>
>>>
>>> Dear Gregor,
>>>
>>> What matters for the BEM computation is the inner skull boundary which
>>> separates the bone compartment from the CSF compartment. The brain surface
>>> is only used to create the source model for imaging source reconstruction
>>> i.e. figure out where the dipoles are located and how they are oriented. If
>>> you just want to put a dipole somewhere inside the head and compute its lead
>>> field you don't need the cortical surface for that. I hope this helps.
>>>
>>> Best,
>>>
>>> Vladimir
>>>
>>>
>>> On Fri, Jan 20, 2012 at 3:03 PM, Gregor Strobbe <[log in to unmask]>
>>> wrote:
>>>>
>>>> Dear SPM experts,
>>>>
>>>> I have a question about the bemcp method to build a BEM model for EEG
>>>> source reconstruction in SPM. Am I right that there are three different
>>>> tissues assumed in the model, including scalp, skull and brain tissue? Can
>>>> someone explain me, how the cortical surface is incorporated in this model?
>>>> Is the cortical surface explicitly incorporated in the calculation of the
>>>> BEM lead fields?
>>>>
>>>> Kind regards
>>>>
>>>> Gregor
>>>>
>>>> --
>>>>
>>>> Gregor Strobbe
>>>>
>>>> Doctoral researcher
>>>> IBiTech - Medisip (Ghent University)
>>>> De Pintelaan 185, Blok B
>>>> BE-9000 Gent (Belgium)
>>>> Tel: +3293324322
>>>> http://medisip.elis.ugent.be/
>>>>
>>>
>>
>>
>>
>> --
>>
>> Gregor Strobbe
>>
>> Doctoral researcher
>> IBiTech - Medisip (Ghent University)
>> De Pintelaan 185, Blok B
>> BE-9000 Gent (Belgium)
>> Tel: +3293324322
>> http://medisip.elis.ugent.be/
>>
>
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