Hi All,
I have two conditions of interest in my GLM analysis, Condition A and Condition B. I would like to make a contrast of Condition A and Condition B that includes only those vertices that are significantly positively activated when compared to the Passive Viewing baseline. In other words, I would like to mask anything that is Passive > Condition A or Passive > Condition B and only include Condition A > Passive and Condition B > Passive when contrasting Condition A and Condition B, so as to limit my contrast to changes in *activation *in the two conditions, not *deactivation *.
I see that in an older version, when isxavg-re-sess was used, there was a flag --trunc that would allow you to set the negative values to 0. If there is a way to do this in the v 5.1.0, I could then perform a second level contrast of positively activated Condition A and Positively activated condition B.
Is there a way to exclude the negatively activated voxels from the Condition A vs Passive and Condition B vs Passive contrasts when looking at Condition A vs Condition B? I would like to do this statistically, not just at the map level.
Thank you for your help!
Maya