Hello Jungho,
there is not absolutely clear solution for this.
"Split DMN" situations are known, see e. g. a recent work in MAGMA
entitled "Increased sleep pressure reduces resting state functional
connectivity"
- it depends, what you want to do with your extracted DMN. If you are
aiming at a group analysis,
I'd rather recommend you perform a group melodic analysis and the move on
to dual_regression analysis
for e. g. a voxelwise analysis.
If you want to stick to individual ICA and extract one DMN by a template,
you can calculate
matching scores, like in Greicius et al. 2006, and check in how many cases
two similar ones are found.
Just adding them up as suggested by you: can be a solution for
illustration, but if ICA separates,
they should rather be seen as "independent"...
vG Philipp
Max Planck Institute of Psychiatry
NMR Research Group
Kraepelinstr. 2-10
80804 Munich
Mail: [log in to unmask]
Phone: 0049-89-30622-413
|