Dear Doug,
Try creating and coregistering a head model in SPM and then press 'Save' and do:
D = spm_eeg_load %select your dataset
mnipoints = spm_eeg_inv_transform_points(D.inv{1}.datareg.toMNI, headpoints)
where 'headpoints' is a Nx3 matrix of your points in head coordinates.
You can then open the MNI template image and check whether the results
make sense.
Best,
Vladimir
On Wed, Nov 30, 2011 at 2:25 PM, Doug Davidson <[log in to unmask]> wrote:
> Dear Vladimir and the SPM list,
>
> I am trying to work out how to transform a set of source locations from our
> Elekta software 'xfit' to the MNI coordinates in DCM for MEG/EEG.
>
> We have fit dipoles in a set of subjects using xfit. For each subject I have
> the x,y, and z coordinates for each dipole in the Elekta system head
> coordinates.
>
> We have also read in each subject's MEG data into SPM, created meshes from
> the subjects' structural MRI, and co-registered the MEG data with the
> meshes.
>
> I would like to fit a DCM model for the source locations corresponding to
> each of the dipoles from xfit, in each subject. Is there a way to transform
> the Elekta coordinates to the MNI coordinates?
>
> Thanks a lot for your help.
>
> regards,
>
> -Doug
>
> Doug Davidson
> Basque Center for Cognition, Brain, and Language
> Donostia, Basque Country, Spain
>
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