Dear Bruno,
There is a tool in SPM8 called Variational Bayesian dipole fitting. It
is described in the manual and in the paper:
S.J. Kiebel, J. Daunizeau, C. Phillips, and K.J. Friston. Variational
Bayesian inversion of the equivalent current dipole model in EEG/MEG.
NeuroImage, 39(2):728-741, 2008.
Using this tool it would be possible to compare the hypotheses that
some source is at location A vs. location B. Note that this tool only
works on a single topography - it's not a spatio-temporal model.
The problem is that I suspect you are talking about MEG and the tool
presently only works for EEG. Christophe Phillips has made some
efforts recently to make it work for MEG but he has not been
successful until now. Perhaps your request will motivate him to
continue working on this now when we are all well rested after the
holidays.
An alternative suggestion is to use DCM for ERP that does work for
MEG. There you can also build two models which differ with respect to
the location of the striatal source (what you should actually do is
put two sources and wire either one or the other in the model). Then
you compare model evidences to see if one is better than the other.
The problem is that you will have to come up with a complete model for
generation of your ERF which might be an overkill in your case. So
theoretically VB-ECD is the right tool.
I hope this helps. I'm CCing my answer to SPM mailing list as the
question is of general interest.
Vladimir
>
> 2009/1/2 Bruno Averbeck <[log in to unmask]>:
>> Hi James-
>>
>> Is there any way to do dipole modeling with SPM? I have a source that is
>> being localized to the insula, right on the edge of the striatum. I suspect
>> it is actually in the striatum? Any suggestions?
>>
>> Bruno
>>
>>
>> Dr. Bruno B. Averbeck
>> UCL Institute of Neurology
>> Sobell Department, Box 28
>> Queen Square
>> LONDON WC1N 3BG
>> E-mail: [log in to unmask]
>> Tel +44 (0)20 7676 2159
>> Mobile +44 (0)79 0313 8392
>> Fax +44 (0)20 7813 3107
>>
>
>
>
> --
> Dr. James Kilner
> Wellcome Trust Research Career Development Fellow and Honorary Lecturer,
> The Wellcome Trust Centre for Neuroimaging
> Institute of Neurology
> 12 Queen Square
> London WC1N 3BG
> Great Britain
>
>
> Tel. 0044-(0)20-7833-7476
> Fax 0044-(0)20-7813-1420
>
> [log in to unmask]
>
> www.fil.ion.ucl.ac.uk/~jkilner
>
>
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