Yes, that is correct. We do this before conducting mvpa analyses for rapid event-related designs.

Ok, if I do not want to modulate each trial in the model, then would you recommend that I use dmBLOCK with a simple stim_times option (no AM1 or AM2)? The documentation online stated, "If different stimuli in the same class 'k' have different durations, you'll have to use the dmBLOCK response model and '-stim_times_AM1' or '-stim_times_AM2', described below." So, I wasn't sure if it would cause problems to use an option other than AM2.

Alternatively, because within a model for an individual trial there is really only one onset time and duration, could I instead just use BLOCK and stim_times? While the run does contain trials of different durations, the individual model only has one trial, so there isn't variation within the model itself.

Thanks!
Heather