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Duration of Stimuli - Important Caveats
¥ Slow baseline drift (time scale 100 s and longer) makes doing FMRI with long duration stimuli very difficult
¥ Learning experiment, where the task is done continuously for ~15 minutes and the subject is scanned to find parts of the brain that adapt
¥ Pharmaceutical challenge, where the subject is given some psychoactive drug whose action plays out over 10+ minutes (e.g., cocaine, ethanol)
¥ Very short duration stimuli that are also very close in time to each other are very hard to tell apart, since their HRFs will have 90-95% overlap
¥ Binocular rivalry, where percept switches ~ 0.5 s