> Lets say I have 2 scanning sessions. In both sessions there are conditions
> A and B resulting in: 1A 1B 2A 2B
> Between the scanning sessions I need to give the participants a different
> set of instructions for how to act during the session e.g.
> Instruction A, start scanning 1A 1B, stop scanning, Instruction B, start
> scanning 2A 2B.
> My question is: when I set up my GLM model can I have 4 columns (1A 1B 2A
> 2B) and compare 1A to 2A (and vice versa)?
That's what I would do - and this is fine
Obviously there is a 'session effect' which is kind of random on the
signal and if any special direction from 1 --> 2 by counterbalancing
this should do the trick
Maybe (I'm not) sure normalization within/between sessions could also
influence the result but I can't tell in which direction ... maybe
somebody out there has an idea?
Hope this helps
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