Hi Daniel,
I should have been more clear with my questions. I am pasting the steps again and the results with the respective units. Basically, my goal was to extract mean beta weights/percent signal changes from the bilateral, left, and right area 6 to double check if those masks are working well, that is, if the means from left + right equal the mean for the bilateral mask. I am trying to figure out why the mean for left + right is way larger than the mean extracted from just the bilateral mask. I feel I need to understand this so that I can trust my numbers. You mentioned above that an oblique dataset may complicate things.
whereami -mask_atlas_region CA_MPM_18_MNIA::Area_6 -prefix mask_B_6_ms
whereami -mask_atlas_region CA_MPM_18_MNIA:left:Area_6 -prefix mask_L_6_ms
whereami -mask_atlas_region CA_MPM_18_MNIA:right:Area_6 -prefix mask_R_6_ms
3dfractionize -template stats.UK002+tlrc -input mask_B_6_ms+tlrc -prefix mask_B_6_ms_fr -vote -clip 0.2
3dfractionize -template stats.UK002+tlrc -input mask_L_6_ms+tlrc -prefix mask_L_6_ms_fr -vote -clip 0.2
3dfractionize -template stats.UK002+tlrc -input mask_R_6_ms+tlrc -prefix mask_R_6_ms_fr -vote -clip 0.2
3dROIstats -nzvoxles -sigma -mask mask_B_6_ms_fr+tlrc stats.UK002+tlrc > BOLD_UK002_mask_B_6_ms.txt
3dROIstats -nzvoxles -sigma -mask mask_L_6_ms_fr+tlrc stats.UK002+tlrc > BOLD_UK002_mask_L_6_ms.txt
3dROIstats -nzvoxles -sigma -mask mask_R_6_ms_fr+tlrc stats.UK002+tlrc > BOLD_UK002_mask_R_6_ms.txt
Side File Sub-brick Mean_1 NZcount_1 Sigma_1
Bilateral mask stats.UK002+tlrc 1[VNS#0] 0.574734 2017 0.959639
Left mask stats.UK002+tlrc 1[VNS#0] 0.712524 991 1.048822
Right mask stats.UK002+tlrc 1[VNS#0] 0.441979 1025 0.844782
Thanks,
Maria