Dear all
I have a rather theoretical question on event-related fmri task design (presently on a 3T, with TR=0.72 and multiband x8)
assuming a fixed recording interval. a visual stimulus lasting 3 seconds.
in general terms (aware that stimuli and task demands affect such answer) it is better to have
200 trials with ITI=2sec. (onsets every 5 sec)
or
100 trials with ITI=7 sec (onset every 10 sec)
or
142 trials with ITI=4 sec (onset every 7 sec)
is there a lower limit for ITI that I should never pass?
thanks in advance
regards
Alberto
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