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Vadim My guess is that the origin of the images is not being set correctly in the small voxel images unless you normalize them. Try displaying an image and clicking the little bar above the image coordinates. This will display the image and crosshairs in relation to the actual origin. You may find that on the non-normalized images the crosshairs are not near AC-PC. If so you will need to re-orient the images so that the crosshairs are correct relative to AC-PC and then redo the stats. Darren On 7/30/08, Vadim Axel <[log in to unmask]> wrote: > > I don't expect them to appear exactly at the right place. I am using > functional localizer technique and I know in advance where more or less my > region should appear. Specifically, fusiform gyrus can't appear in frontal > lobe. The less preprocessing we do the better, so I prefer not to make > normalization when I can localize my ROIs without it. > > On Wed, Jul 30, 2008 at 3:36 PM, John Ashburner <[log in to unmask]>wrote: > >> If images are not spatially normalised, then there is no reason why the >> activations should appear in the appropriate place on the glass brain. >> What >> I can't figure out is why you appeared to get the activations in the right >> place when using your normal resolution data. >> >> Best regards, >> -John >> >> On Wednesday 30 July 2008 12:00, Vadim Axel wrote: >> > Hi, >> > >> > I am scanning with the following voxel resolution: 1.56 x 1.56 x 2.4 >> > Unless I do normalization (voxel size: 2x2x2) I am getting the >> activation >> > totally misplaced in glass brain (see not_normalzied screenshot; the >> > activations should be in temporal - occipital regions). Normalization >> > solves the problem (see normalized screenshot). With normal resolution >> > scanning (voxel 3.13 x 3.13 x 4) I get standard activations without >> > normalizing data as well as with normalization. >> > >> > Any idea? >> > >> > Thanks, >> > Vadim >> >> >