Global mean regression removes all voxels?

Submitted by nertman on Sat, 05/18/2013 - 01:25

Hi, I have been using DPARSFA for preprocessing and it has been working very well so far. I tried to remove the Global Signal nuisance regressor, but after doing so my data has no voxels left -- i.e., when I enter it into a first-level model in SPM, and estimate the model, I get this popup message:
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No inmask voxels - empty analysis!
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And this command line error message:
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Reference to non-existent field 'xVol'.
 
Error in spm_getSPM (line 243)
XYZ  = SPM.xVol.XYZ;                %-XYZ coordinates
 
Error in spm_results_ui (line 263)
        [SPM,xSPM] = spm_getSPM;
 
Error while evaluating uicontrol Callback
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I've had the same thing happen regardless of the level of preprocessing that has been done. When I skip the global signal regression everything runs fine. What might be the problem?