errts file in afni_proc

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1

Hi everyone,

I am preprocessing some resting state date with afni_proc.py. I understand the errts image is basically the image file after the regression analysis. What’s putting me off a little is that there are non-zero voxel values outside the brain mask. All of the other prior outputs seem fine. I am not sure if this is standard (need to apply a mask later to limit non-zero voxel areas to the brain) or there is something wrong in the analysis. I am attaching an image (slice) of the errts file alone and overlayed with the brain mask.

Thank you very much and I appreciate your help.

Regards,
George

e.bmp (10.3 KB)

em.bmp (10.3 KB)

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Hi George,

By default, single subject analysis is performed with only
minimal masking (masking out voxels where data is missing).
No brain mask is applied unless it is asked for.

See “MASKING NOTE” in the output of afni_proc.py -help,
and the sub-section “Why has the default been changed?”,
in particular.

  • rick