Hi Peter,
Thanks for your input.
It's still unclear to me using -paired option. That is to contrast two sessions, which is not what I am interested in.
I want to see a main effect of stimulus onset activity (against 0) in overall collapsed across two sessions. Also entering covariates would be subject-wise, not session-wise in 3dttest++, which I assume covariate regressor would not be able to account for the inter-session variability..?
It would be much appreciated if you could provide more detail - maybe I'm missing some options...
Thanks a lot for your help.
SJ
