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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 -- ____________________________________________________ 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 [log in to unmask] http://www.medizin.uni-tuebingen.de/kinder/epn/ ____________________________________________________