Hi everyone,
I have a somewhat (basic) question regarding 2nd level analyses. I have been conducting my analyses such that at first level I'll specify my contrasts (i.e., task vs baseline), and then at 2nd level I run a t test entering "1" when defining my contrast. I heard once that it is better to run only main effects at 1st level, and specify your actual contrasts at 2nd level (though I can't remember the rationale for this).
I'm just wondering if anyone has any insight into this (e.g., is the activation more robust in one case versus another), and why it would make a difference when you specify your contrast.
Thank you,
Meera
Meera Paleja, B.Sc. (Hons.), M.A.
PhD. Candidate, Psychological Science
Brain Imaging and Memory Lab
Department of Psychology
Ryerson University
Toronto, Canada
Phone: (416) 979-5000 ex. 2192
email: [log in to unmask]
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