Using ICBM Probabilistic Atlases

[Vladimir Litvak]

Just one slightly simpler idea. If you have a structural image of your
subject that you use for  beamforming and there is a structural that
comes with the atlas you can coregister these two (that can be done in
SPM) and then (given that you know how the space of the subject's
structural relates to the beamformer space) you won't need any
fiducials.

Best,

Vladimir

On Fri, Jun 13, 2008 at 6:45 PM, Vladimir Litvak <v.litvak at ion.ucl.ac.uk> wrote:
> Dear Will,
>
> I haven't use these particular atlases but I've recently worked on a
> similar problem. Basically you can interpolate your source data on any
> MRI.  To do that you should set the source.transform field (where
> 'source' is beamformer output) to the transformation matrix from the
> coordinate system in which you did the beamformer to the coordinate
> system of the target MRI. Then you call sourceinterpolate() with that
> modified source struct and the target MRI as inputs.
>
> To get that transformation matrix you will need some fiducials and
> with that I can't help you. If that atlas has a corresponding
> structural image you can load that image with some software (I use
> SPM) and click on some landmarks to find their coordinates. You can
> then find the coordinates of the same landmarks in your beamformer
> coordinate system. Of course the precision of your coregistration will
> depend directly on how precisely you can define the fiducials in the
> two systems. Given at least 3 matching landmarks the transformation
> matrix can be computed. How it's done exactly depends on some details
> that I wouldn't like to get into here.
>
> If you don't get better help, write me and I can try to share what I know.
>
> Best,
>
> Vladimir
>
>
>
>
> On Fri, Jun 13, 2008 at 5:20 PM, Will Findley <findley at gmail.com> wrote:
>> I would like to localize activity onto the ICBM probabilistic atlases from
>> LONI.  It is unclear to me how and where I should modify the DICS
>> localization procedure to utilize them (particularly the tissue atlas).  I
>> also do not know how to obtain fiducial positions for them.  Does anyone
>> have experience localizing onto these atlases that would help?
>>
>> Thanks,
>> Will
>>
>> ----------------------------------
>> The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/fcdonders/fieldtrip.
>>
>>
>

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The aim of this list is to facilitate the discussion between users of the FieldTrip  toolbox, to share experiences and to discuss new ideas for MEG and EEG analysis. See also http://listserv.surfnet.nl/archives/fieldtrip.html and http://www.ru.nl/fcdonders/fieldtrip.