Hi Tim,
The point of your question may be eluding me. I do not
see why the order of the stimuli has any relevance to
how it is analyzed.
It would be fine to make 2 row timing files (1 row per
run) for each of the 3 classes. That the times on the
2 rows differ does not matter to afni_proc.py.
Or are you thinking to compare the classes across runs?
If so, then they are not the same classes, in which
case you would have 6 classes. Each timing file would
still have 2 rows, though 1 would just have '*'.
- rick