there a way with Marsbar (or > another script) to create ROI masks with different dimensions (say > 151x188x154)? Or is there a way to easier convert the 91x109x91 images > to 151x188x154? You can set the default 'base space' for ROI images in the options menu, by choosing an image with the dimensions and voxel sizes that you want. Does that help? Best, Matthew