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Dear SPM-Users, i am currently reanalyzing a fMRT-dataset in which the subjects did 4 conditions in the same succession. The first step of the analysis was realigning and unwarping the scans, using the following parameters: Estimation Options . Quality: 1 . Interpolation: 7th Degree B-Spline . Wrapping: Wrap Y Unwarp Reslicing Options . Interpolation: 7th Degree B-Spline . Wrapping: Wrap Y All other parameters were set to default. The graphs showed heavy movement (up to 15mm) of all the subjects, but ONLY between the first and second images of the first condition and always in negative-X-direction. It seems implausible that all the subjects really did move in the same direction at the same point of time, so we do assume that there is an error in our data/analysis that causes this pattern of results. Interesting is also that all subjects and conditions were analyzed using a batch, and that the 'movement' only appears at the beginning of one condition and not all of the conditions. Since the data was previously analyzed with spm2 (usingthe same parameters), we compared the results with the allready existing ones. As you can see in the attatchmed image, if you discard the first image, the graphs are virtually the same. The exeption of this pattern is the rotation in the first condition (Condition 002), which does also have rapid changes both in positive and in negative direction between the first and second image. We had the idea that we could maybe work around the problem if we simply exclude the first image from analysis (and reduced the onsets of the stimuli etc by TR), but we are not sure if this is an adequate solution. So I would be gratefull if you could tell me if there if you did previously encounter this problem and can tell me it's origin, what your solution was and if our way of attempt of working around it is adequate if we don't find another solution. Best regards, Max Hilger