Hi all,
I'm trying to do PPI in SPM8 and have been using the PPI button on the main GUI to create my PPI terms, the way I have done in SPM5. I have done this for almost 60 people for 3 runs.
I've just realized that PPI is now included separately in the job/batch editor under task>stats> which will create the PPI terms for all three runs together. I'm wondering whether there are any other differences between the two methods? Basically, do I need to re-create the PPI files using the new all-in-one way?
I've tried to check this out myself by creating the PPI terms for one participant using the new method and comparing them to the old method that can still be used in SPM8 but I'm struggling with understanding the 'input variables and contrast weights' part. If any one could shed any light onto this for me that would be great. I've checked the manual and see that column one is SPM.Sess.U(i) and second column is SPM.sess.Uiiname but I'm struggling to understand what this means.
Please forgive my ignorance!
Any help at all would be much appreciated,
Kindest regards,
Sophie
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