hi,
i'm interested in creating a mask from my group-level activation map, in only a certain region. we've used 3dcalc -astep to threshold the map, and now we'd like to constrain the mask to our ROI. i realize that i can multiply the thresholded image by a sphere, or some other shape, but i was wondering whether there is a way in AFNI to actually TRACE activation in only a given region and create a mask from that. in other words, we'd like to be able to SEE the overlay while we create the mask.
help is much appreciated.
thanks!
fanny
