> ...but I'm not sure how to derive the percent signal change at a specific coordinate in the activation map.
If you just want to know the percent signal change at those two voxels, you can use load the output from 3dcalc with the afni image viewer, and navigate to those two voxels, and find out the values.
Also you don't really have to run 3dcalc. Instead you can use AFNI viewer to find out the values of SRFvB and SRSvB at those 2 voxels, and calculate the difference yourself.
> My questions on the theoretical significance and t-test from my last post still stand.
If you want the difference of RFvB and RSvB at individual level, it is essentially the difference between RF and RS, so add a line with option gltsys for RFvRS.
Gang
