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Dear SPMers/SnPMers, I am doing a non-parametric second-level analysis (12 con images) with SnPM-99. I understand that there is no "SVC" option in SnPM, however could I still anyhow benefit by having a spatially-constrained hypothesis about activation? For the sake of experiment I tried to perform an SnPM99 analysis on con-images previously masked by a VOI. I noticed that the "critical threshold" reported at the bottom of Table is lower for the VOI analysis then for the whole brain analysis, both were done with the same variance smoothing, number of permutations, thresholds (voxel p<0.05, no extent threshold), etc. Moreover the VOI-based analysis revealed a significant activation that did not show up during the whole-brain analysis. However I doubt that this is the right thing to do... :/ any comments please? thanks! Victor ********************************* Victor Vorobyev Centre for Cognitive Neuroscience Department of Psychology University of Turku Finland *********************************