Regressor files are organized in the following format in seconds: ONSET: DURATION. The duration of the events in each regressor should be the same, though sometimes there are very slight variations in the duration times (milliseconds) due to computer processing variations, so I wanted to specify the duration times in the regressor to model the events as accurately as possible.
For my afni proc script, I specified the regress_basis to be dmBLOCK, though I am not quite sure whether the stim_times should be AM1 or AM2 or whether I need to specify a specific stim_times. I read through the “AMRegression” information online but I am still not sure which option is appropriate.
I appreciate any help or suggestions you can offer.