Hi Amy,
> I'd like to do an fMRI experiment wherein, instead of taking the
> subject template to MNI template, I need them in their native space. MAy
> I know how to perform such experiment?
This will actually be easier on the first level as you simply skip the
step of spatial normalization :) It becomes slightly more tricky
afterwards but not overly so: instead of normalizing all EPI images, you
now only normalize the con-images and perform second-level statistics on
these. One issue to be aware of is that more extensive interpolation
schemes (such as higher level b-splines in spm) will lead to
out-of-brain voxels not being absolutely 0, which may interfere with
mask generation. You can use an explicit mask to that effect.
Incidentally, I think this is actually the preferred approach:
mathematically, they should yield pretty much equivalent results but
they don't. The issue, of course, is interpolation, and without having
explored this exhaustively, I believe that one can make the case that it
is better "to interpolate" the results (generated from non-interpolated
raw data) than "to interpolate" the raw data. But that is only my 2 cents.
Cheers,
Marko
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PD Dr. med. Marko Wilke
Facharzt für Kinder- und Jugendmedizin
Leiter, Experimentelle Pädiatrische Neurobildgebung
Universitäts-Kinderklinik
Abt. III (Neuropädiatrie)
Marko Wilke, MD, PhD
Pediatrician
Head, Experimental Pediatric Neuroimaging
University Children's Hospital
Dept. III (Pediatric Neurology)
Hoppe-Seyler-Str. 1
D - 72076 Tübingen, Germany
Tel. +49 7071 29-83416
Fax +49 7071 29-5473
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http://www.medizin.uni-tuebingen.de/kinder/epn/
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