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> I have some questions about preprocessing of fMRI data sets. My > preprocessing steps are : > > 1. realignment of the functional volumes; > 2. coregister of the mean functional volume and the structure image(T1); > 3. Normalise functional image with T1 template and T1 structure image. > 4. smoothing the result of normalise with a FWHM 2-3 times of the voxel > size. > > Are these steps correct? > > Some users don't coregister between the functional image and structure > image. And they normalise the functional images with a EPI.mnc. Which > method is better? This question can only be answered empirically. Whatever works better will depend on your images. This includes whether their contrasts are similar to the SPM templates or not, and also the artifacts they contain. For example, if your EPI images are distorted, then you won't achieve a good registration between the anatomical and functional images. If this is the case then applying warps estimated from the anatomical images to the functional images is unlikely to work well. Any method or model is only valid with respect to the data that it is to be applied to. This validity will depend on whether the model assumptions hold for that data. Best regards, -John