We have a very simple, technical SPM5 question with respect to VOI
extraction for PPI analysis.
When we want to extract a VOI from every subject on the 1st level
(fixed effects), it requests to choose session 1, 2, 3 OR 4 (since
four sessions were modeled) but of course we would like to extract the
adjusted time-series throughout the ENTIRE experiment (e.g. all four
sessions). Is there anything we can type in there so it allows us to extract an
adjusted VOI from all 4 sessions at a time (we tried entering 1:4, 1234 and
1,2,3,4 but it keeps saying "scalar required")? If this is not possible, do we
have to extract VOIs separetely for all 4 runs and combine them somehow
afterwards for the new PPI first level? If so, how is this done?
Thanks a lot for your help, it is much appreciated!!