Hi again AFNI experts,
I'm building a PPI analysis for a block-design task (2 stim types have blocks 14 sec long, 1 stim type has 46 sec blocks). In the spirit of making this as robust an analysis as PPI can be, is it appropriate to use a GAM HRF (like Gang has on his page through waver) or would a block HRF be better (as through 3dDeconvolve -nodata options).
It seems a block HRF would be more appropriate conceptually but I can't find it actually used anywhere so I'm wondering if I'm missing something with this PPI step? Can one of you clarify for me?
Thanks so much!
Cheers,
L
