Hi all,
While trying to model an event-related design with FIR basis functions, I am getting different timecourse results for our group-level analysis if I use custom 1-column EV's vs. 3-column format.
I am looking at ROI's in primary visual cortex for simple, canonical fir hrf's but the outputs are distinctly different depending on our input EV format. I've rechecked to make sure our files are coded up correctly, and everything looks consistent.
Questions: is there something extra the 3-column format does during convolution (i.e. is FEAT taking into account the event duration column?) versus the 1-column files? Is one format correct/preferred over the other?
If anybody can point me in the right direction or has any guidance to properly extract timecourses, it would be greatly appreciated!
Thank you,
Neil
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