Dear FreeSurfer experts,
for the analysis in QDEC I created my own Monte Carlo correction. My questions relate to the threshold option.
1. Would I use neg if I have mostly blue clusters in the QDEC display and pos if I have mostly red clusters?
2. When do I use abs?
3. I compared the neg option at different thresholds (1.3, 2.0 and 2.3) and I get different clusters: 1.3 (=.05) # ClusterNo Max VtxMax Size(mm^2) MNIX MNIY MNIZ CWP CWPLow CWPHi NVtxs Annot 1 -2.669 76591 1148.00 -6.7 14.5 62.7 0.00880 0.00760 0.01000 1600 superiorfrontal 2 -2.443 91912 2128.78 -10.3 55.3 -23.5 0.00010 0.00000 0.00020 2971 medialorbitofrontal
2.0 (=.01) # ClusterNo Max VtxMax Size(mm^2) MNIX MNIY MNIZ CWP CWPLow CWPHi NVtxs Annot 1 -3.289 92754 420.03 -36.5 57.0 -21.0 0.02140 0.01960 0.02330 571 parsorbitalis 2 -2.669 76591 428.11 -6.7 14.5 62.7 0.01940 0.01760 0.02120 604 superiorfrontal
2.3 (=.005) # ClusterNo Max VtxMax Size(mm^2) MNIX MNIY MNIZ CWP CWPLow CWPHi NVtxs Annot 1 -3.289 92754 314.80 -36.5 57.0 -21.0 0.01900 0.01730 0.02080 410 parsorbitalis
Technically, if parsorbitalis is significant at .01 and .005, shouldn't it also be significant at .05? I've compared the clusters in freeview and the superiorfrontal is the same cluster in both 1.3 and 2.0. The parsorbitalis and the medialorbitofrontal clusters are completely different, not even closely overlapping.
Do you have any idea why that is and what it does differently? Thank you! Cheers, Clara