Dear SPMer,
I want to analyze differences in connectivity in two groups of patients & got some basic questions regarding the design:
My fMRI design:
- event related
- participants see emotional & neutral pictures
- after scanning participants had to remember the images
- first level GLM matrix has the following regressors:
1.emotional remembered (ER)
2. emotional not remembered (EnR)
3. neutral remembered (NR)
4. neutral not remembered (NnR)
- second level group comparison reveals higher activity of the patients for the contrast (ER > EnR) in the insula
Now I want to explore differences in connectivity for ER > EnR between the groups using the seed region insula
My PPI questions:
1. Extracting VOIs
a) Which contrast should be used for extracting VOIs?
Remembered > not remembered?
b) During extracting VOIs: should data be adjusted for effects for interest
(F:contrast
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1)
2. Create PPI variable
Include ER -> yes 1
Include EnR -> yes -1
Include NR -> no
Include NnR –> no
Thanks in advance & happy new year to all!
Ben
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