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Hello list, just out of curiosity, I analyzed a fairly complex (and long) erfMRI experiment with a 3x3 factorial design with both SPM2 and FSL3.2b. I tried to keep everything as close to the other package as possible, i.e. I adjusted both smoothing kernels to 5mm, set the high pass filter to 128s, used gamma function + temp. derivative in FSL (standard delay) / canonical hrf + tdv in SPM2, entered identical onset vectors, specified identical contrasts and so on. I set the duration for my events to the actual 1.5 seconds in both packages, as FSL doesn't allow 0-durations. Now one of the packages gave me "blobs" on a corrected-for-multiple-comparisons level of 0.05, where the other didn't show anything worth mentioning on a uncorrected p=0.001 level. Is that possible at all, given the similarity of the statistics? Has anyone experienced something similar? I am aware of the comparison done by Bianciardi et al (NeuroImage 2004), but differences were marginal at best...! Thanks for your help, Yours, Cornelius -- Cornelius Werner Institut fuer Medizin (IME) AG Kognitive Neurologie Forschungszentrum Juelich 52425 Juelich Germany Tel. +49-(0)2461-61-8609