Dear Martin,
> Hi Cyril,
> Thank you very much for the article. My problem is that there is no
"baseline" in my design, only 11 conditions of
> interest. What do the deactivations mean in that context?
>Martin
As I explained to you in the previous e-mail, the positive activation
observed for the contrast A-B>0 means that A>B with either A more
positive than B or A less negative than B. The result of A-B>0 is the
same with or without baseline. If C is a baseline A-C>B-C = A-B>0 !
In your ev-fMRI design, the implicit baseline is no activation (mean
intensity) instead of a control condition (also called baseline). To
check that this positive difference between conditions could be related
to deactivations, you can look first at your simple effects (do you have
any activations in this region for only A or only B?) and second compute
the intensity of the signal in this region (with Marsbar for example)
Good luck,
Best,
cyril
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