Hi,
I'm modeling an experiment in which participants select an action (and immediately execute it) after seeing a cue. The duration of the action selection process is different in two different conditions (i.e., RTs are longer in one condition than in the other). Mean RTs are in the 400-550 msec range.
My hunch is that I should just set the duration in the 3-column EV format to "1" and the beta weights will be sensitive then to a combination of duration and the instantaneous amount of neural processing - i.e., they will be related to the sum of physiological activity over that period of < 1 second. Is there any reason to use a different duration for different responses? Or a shorter or longer fixed duration?
I have a 2 second TR if that's of any relevance here.
Thanks!
Dav
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