Hi Everyone,
I am working on a fMRI event related memory experiment with 3 groups of subjects.
Experimental design
1) 8 sessions
2) 4 encoding sessions alternate with 4 retrieval sessions
3) Design matrix were created seperately for encoding and retrieval with one condition in each so that
encoding and retrieval sessions can be considered as different experiments.
4) Two First level contrasts (.con images) were created for each subject, one to look at the deactivation during
encoding sessions and one for activation during the retrieval sessions.
I wanted to do a 2nd level conjunction analysis between encoding and retrieval contrast images of all subjects within a group.
For example if group 1 has 5 subjects and each subject has a contrast image for encoding and one for retrieval. So i have a total of 5 encoding contrast images and 5 retrieval contrast images for the whole group. I wanted to make a conjunction analysis between these 5 encoding and 5 retrieval images.
I tried doing this by using ANOVA in SPM8 where i created two cells . In one cell i added all the 5 encoding contrast images and in the other cell added the 5 retrieval contrast images. I defined a F- contrast [1 0
0 1].
But i am not sure what i did was correct..
Is what i did i correct? If not please let me know how do i do it..
Thank you,
GOkulraj
|