Hello,
I am starting use FSL for my analyses for the first time. I am conducting an
experiment with jittered event-related design, therefore I am using 3-column
format to analyze the data. I understand that the data needs to be
organized, by <onset> <duration> <1 or 0, depending on whether it is of
interest>.
In the datafile created by my stimulus program, my first MRI scan and object
onset corresponds to an onset time of 363 ms (and not 0 ms), because the
script has instruction screens etc that take up the first 363 seconds.
Since, I'm using the onsets from the script, is that a problem that the
first event and MRI scan chronicle it occuring at 363 ms and not 0ms?
Also I am using a jittered trial design with an average trial length of 8
seconds. Does duration refer to duration of stimulus (which is 650 ms) or
duration of that specific trial? If it is the latter, I have a compound
trial type with a first stimulus and jittered timing of 300-400 sec then a
second stimulus and then jittered timing of 270-370 sec.
Thanks for your help!
Vina Goghari
Graduate Student
University of Minnesota
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