Hi experts,
Here is an uncommon design of fMRI experiment. It's a 2x2 factorial design. Each trial lasts 15 TRs (TR=1.5 sec) in which three images are consecutively displayed in the first three TRs. Subjects perform a memory task when seeing these three images. The following 12 TRs are blank during which subjects have a rest. My question is : during the "specify 1st-level" step, should I define 0 or 3 to be the Durations of each Condition. In other words, should this uncommon design be deemed as an event-related design or block design to get reasonable statistical parametric map? Thanks for any assistance!
Cheers,
Min
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