Dear SPMers,
I would very much appreciate help on the following problem:
I am comparing 2 groups of subjects on an n-back task. Both groups performed 0-, 1-, 2- and 3-back conditions. I use 0-back as baseline and compare the groups with 2 -sample t-test for 1>0(grA) vs 1>0 (grB), 2>0(grA) vs 2>0(grB) etc
However, I suspect that the baseline condition activation(0-back) is very different between the 2 groups, which would make my 2-sample ttests difficult to interpret..
I did a "direct" comparison 1-back(grA) vs 1-back(gr B) etc, but of course it does not remove the intersubject/session variability and it is thus difficult to know which differences are relevant.
Does anyone have an idea for testing for differences between the baselines?
Thank you very much!
Olga
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