Hello,
Sorry for being slow on this. Sure, you can use the EXPR(b,c) basis function to have a response last from post-stim time 'b' to 'c'. In this case, maybe the expression should just be 1.
For example, if you had tr-locked events on a 2-second grid that lasted for 10s then consider: 'EXPR(0,10) 1'.
But note that since it includes times at 0 and 10, it will cover 6 time points, not 5. To have only 5, do not quite include the final 10 s offset: 'EXPR(0,9.9) 1'.
If the events are not TR-locked, you may have to think about what to do when the stimulus lasts for a fraction of the TR. In such a case, timing_tool.py might offer more flexibility. For example, consider the same scenario (10s events, TR=2), but not TR-locked. If you want to include any time point that has at least 30% stimulus time, and if there are 2 runs with durations 300s, consider something like:
timing_tool.py -timing timing.txt -timing_to_1D STIM.1D \
-tr 2.0 -stim_dur 10 -min_frac 0.3 \
-run_len 300 300
Consider examples 6 a,b,c in the output of
timing_tool.py -help.
- rick
Edited 1 time(s). Last edit at 10/23/2019 09:49AM by rick reynolds.