Hi! I have a quick question about whether it's appropriate to use an FIR model for a
variable duration trials.
If each scan starts at time 0, and runs til time 2000ms;
1. Participants see a cue from scan time 0-500ms, a blank screen at time 500ms which then
disappears at time 700ms.
2. TASK: at scan time 700ms everyone sees the task stimulus appear. This remains on
screen til at least time 1300ms (and potentially til time = 2000ms).
3. IF the task stimulus ends before 2000ms, a blank screen is shown til the end of the TR.
As everyone is doing the task at the middle of the scan acquisition, is it ok to use a FIR with
data slice-time corrected to the middle of the TR (i.e., time 1000ms) and interpret the
results as reflecting task-related activity?
Thanks
Chris
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