SimpleROIBuilder for SPM2 Toolbox
 
Ever wanted a very very simple way to make a mask (0's and 1's) specifically for ROI analysis (such as if you use my ExtractVals or Deconvolver tools)?
 
I have whipped together a little tool for spm:
 
 
Download and drop in your toolbox directory, it is then available under the toolbox pull-down menu in SPM2 (should work in SPM5 as well).
 
You can drop spheres and boxes onto a volume. To use do this:
 
   toolboxes -> SimpleROIBuilder
 
1) You are then prompted for how many rois' you would like to place in the volume to be created.
 
2) You are asked to pick a volume for dimension and voxel size matching. If you are wanting to extract values from your contrast images etc, just pick one of those as a reference. (Remember the canonical brain is 2x2x2mm voxels)
 
3) You are then prompted for the name to give the mask image to be created. This will be created in the current working directory of matlab - so be careful not to overwrite some other file.
 
4) For each ROI blob to be created you are prompted for:
    
         a) Center of ROI (in millimeters) (you can get these from your activation maps or standard atlas (MNI))
         b) Sphere or BOX
         c) if Sphere then the radius, else
             if Box then the size in along each dimension
 
Also, you can make complex looking ROI's by make seperate images of the parts of the ROI and then use the "imcalc" tool in matlab to do math on your volumes. (Rememeber if you want to take the intersection of two volumes you need to specify the multiplication the ".*" not just "*". The "." (period) is crucial.)
 
Let me know if you have any issues with the new tool.
 
Have FUN!
 
Robert Welsh
rcwelsh at med.umich.edu