Hi,
I have a problem now. When I computed the percent signal change using
featquery for event-related data, I found some results are strange. For
example, in one ROI, the max psc is 9.32, and the min psc is -17. So I tried
to find what is the problem with it, and I found the value of the
correponding voxels is very low, about 5000. But, actually, values of most
voxels should be around 10000. What's the problem?
In my research, I defined ROIs, such as FFA, Amygdala, OFC etc., by
using random-effects group activation with all faces vs. baseline. And I
created spheres using coordinate of peak activation in the group activation
as center. Then I intersected the sphere with group level activated map and
obtained the functional mask. Then I applied the same mask to individual
subject for specific ROI, and computed percent siganl change(PSC) with
several contrasts.
Thanks a lot!
Xiaoyun
