Hi All,
I am analyzing a task using GLM FLEX. I have created a 2x2 repeated measure anova.
I have some questions, some of those are quite basic, some others not (I guess).
1)Let say I have SESSION and CONDITION as factors, then in I.scans I should insert something like
SUB1_SESS1_COND1
SUB1_SESS1_COND2
SUB1_SESS2_COND1
SUB1_SESS2_COND2
SUB2_SESS1_COND1
SUB2_SESS1_COND2
....
SUBN_SESS2_COND2
Am I right?
2)I have created contrasts on the main factor of session (in both directions) inserting
I.Cons(1).Groups={1 2}
I.Cons(2).Groups={2 1}
because in that way you create two on-sided t-test, right?
Now, I got some results and want to analyze them using FIVE, but have some troubles.
3)Just to be sure I am doing it correctly, with FIVE you can do statistical inference by putting T(F)-contrasts into the viewer, then clicking on FDR and FWE; in that case, given all estimate outputs of the analysis are in the same folder, FIVE will pick the correct error term to make such inference, am I right?
4)FDR and FWE mc corrections are done at peak level, am I right?
At this point I get something weird, since using FDR I get a lot of activactions, whereas with FWE no voxels survive thresholds. Is it possible? Looking at the thresholds, using a corrected alfa of .05 fdr p-threshold is +0.0164, which is quite big I guess, whereas with FWE threshold is 2.7e-07. Why so much discrepancy?
5) Is it possible to change color limits of activation bar?
6)I do not understand items of Parameters menu within FIVE. What is sign about? And what about Peak Number Limit and Peak separation?
7) What would be a good choice for an atlas to know anatomical locations of peaks? AAL version available is v4, is it possible to import other ones? (e.g., I can select Harvard Oxford cortical atlas, would it be possibile to insert also the sub cortical one?)
8)What is the direction convention of FIVE? Neurologic (right is right), or radiologic (like FSL?)
7) If one wanted to look at cluster level inference, how would that be achiavable? Is there a way to feed data in SPM for looking at cluster level thresholds?
A know I made a lot of questions, but I haven't found a manual and I am new to GLM FLEX.
Thanks a lot in advance,
Alessandro
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