Dear AFNI experts,
I am using TENT(0,20,11) in 3dDeconvolve with option “-iresp” to estimate impulse response to the stimuli onset.
(Here, TR = 2 sec)
In the event-related design, time difference between the onsets of the visual stimuli are ranged from 4 sec to 12 sec (InterStimuli-Interval: ISI).
Is using 11 TENT coefficients acceptable given that the ISI ranges from 4 sec to 12 sec?
I would like to estimate the impulse response in hippocampus, which is known to respond slowly after stimuli onset.
That is why I need to capture the response up to 20 sec, however, I am concerned that I cannot reliably estimate the response because of
short ISI in my experiment design.