Hi all
i have a problem with my results produced by spm 5.Basically i am trying
to plot the reponses of the subjects with respect to 3 conditions:-
instruction cue(0.3sec) follow by
variable delay(1.3-20.8sec(steps of 1.3sec)) follow by
trigger cue(0.3sec)
I am trying to find out what is the different responses which the subjects
will give during each of the different conditions.By right, the response
given by the subjects during the trigger condition should start later than
the instruction condition , however the graph of the two condtions i have
got have the same starting response time when plotted.
The trigger graph should have no response for at least the 1st 10secs, but
it is giving some activation.Can anyone advised on this? How do I get a
lag in my BOLD signal response to differentiate between these 2
conditions? Do I add delay condition into the 1st level too when modeling
instruction and trigger?
I modeled the instruction and trigger using gamma bf window duration
37.7sec, order 6.
Thanks alot.
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