> What is the GLT output when I'm not specifying the basis function? Does it combine the two basis functions (and how does it do it?)?
If you don't specify the basis function index, 3dDeconvolve gives you the sum of those two regression coefficients, which would not make much sense.
> Which one should I use for the group analyses if I want to compare the first basis function and the combination between the first
> basis function and the derivative (t test with permutations)?
There are two possibilities. You can focus on the first basis function and ignore the second, which seems to be the norm in the SPM-land:
-gltsym 'SYM: S[0]'
Or, you can adopt an omnibus approach:
-gltsym 'SYM: S[0] \ S[1]'
which is the same as
-gltsym 'SYM: S[[0..1]]'
See more details here: [
afni.nimh.nih.gov]
Gang
Edited 1 time(s). Last edit at 03/01/2021 06:56AM by Gang.