Dear all,
I would like to analyze fmri data acquired with a sparse design:
TR=1,5 sec, Interscan Interval 9 sec, stim duration 3 sec. , fixed stimulus onset 0.2 sec
after vol. acqu. , 4 conditions(ABCD) and a pseudorest cond inbetween different
condions
12xA -3R- 12xB -3R- 12xC -3R- 12xD -R- ...
So far I basically the following questions:
1) If I modell with Gamma functions, what would be the best window length ?
2) Should I model every single event or one condition as one "block"
3) What would be the best way to assess the main effect and the differential effect?
1 1 1 - 1 -1 -1 for A-B or -1 0 0 1 0 0 ?
Any suggestions ? or corrections?
Many thanks in advance!
Lukas
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