In the past we used older versions of 3dDeconvolve with the -stim_file option, and used -stim_minlag and -stim_maxlag to offset the hemodynamic models. Then, an iterative regression was used to fit the different models to the signals from each participant, and we used the best-fitting model for further analysis. We would now like to switch to using -stim_times, but we're not sure how to offset the model created with one of the 'Rmodels' listed in the help file for the current 3dDeconvolve. We would like to use the recommended -stim_times options, but how can we offset the models created with a TENT or BLOCK function?

Thanks for your help.