sourcestatistics: what to compare?

[Floris de Lange]

Dear Fieldtrippers,

I have a question about what conditions/comparisons make most sense to
statistically compare with sourcestatistics.
I have 2 conditions, A and B, and each condtion has its own pre-stimulus
baseline: basA and basB.

Now, first I'd like to see which regions are showing stronger beta-band
power during A than the baseline. So I want to compare A to basA.
There's 2 ways of going about it:
1) compare (the grand average of) A.avg.pow with basA.avg.pow
2) compare (the grand average of) the neural activity index (NAI) of A
with the baseline

Any ideas which would be best? Or is this just an empirical issue?
(i.e., take the best)

To compare A and B, one has even more options:
1) compare A.avg.pow with B.avg.pow
2) compare (A.avg.pow/basA.avg.pow) with (B.avg.pow/basB.avg.pow)
3) compare NAI(A) with NAI(B)
4) compare NAI(A)/NAI(basA) with NAI(B)/NAI(basB)

Is there's any principled reason for a priori picking any of the above
choices?

Your input is greatly appreciated,
Kind regards,

Floris