EPI distortions and dropout mean that the rigid-body model is not always
appropriate for within subject alignment of EPI data. Even if the brain
moves in a rigid way, there may be distortions in the images that are in
need of correction.
Best regards,
-John
On Mon, 2010-02-15 at 11:13 +0100, Javier Moya wrote:
> > Hi all!
>
> I have a problem with my overlay, a customized template done by corregistering anatomical images from 4 subjects.
>
> The activations I got are ok, but they seem to have an offset (and thats the problem i would like to solve). I paste two images. In the first one i'm using as a overlay the anatomical template. In the second one my overlay is a realigned, normalized functional image. As you can see, the second one localizes exactly the electrode is used for this experiment; unfortunately there is an offset in the first one.
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> I made a check reg of my anatomical template, a mean of mean images of each subject in the experiment and one religned, normalised funcional.
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> Does anybody know what could be happening? In normalization process I change the voxel size of functionals from 3.125 3.125 10 to 3 3 3 where source images are the mean of functionals of each subject and template the mean of means of all subjects. Should I change some parameter at anatomical template header?
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--
John Ashburner <[log in to unmask]>
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