Marko Wilke's reply to the first question is really exhaustive.
About the second ...
I am not too expereinced, but ... what do you mean that your blocks are
as separate sessions?
If you've got for example three conditiond, A, B, C (one of which is
rest) you repeat in separate sessions A B C A B C because it would get
too long to do A B C A B C A B C A B C, or you do A B A B A B in one
session and A C A C A C in another session and so on?
I know that one can just put the data from separate sessions one after
the other, but ... Is the difference between sessions only in the motion
parameters? I think there is something more going on.
Can't you just treat them as separate sessions and combine the results
by selecting the appropriate contrast?
If you do that, for each session you can include the corresponding
motion parameters.
Is there a particular reason why you don't want to do that?
Laura
-----Original Message-----
From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]]
On Behalf Of Markus Burgmer
Sent: 06 February 2007 09:54
To: [log in to unmask]
Subject: Re: [SPM] motion correction
dear list.
sorry that i have to bother about motion correction again. but there is
one
replyquestion of laura still unanswered and another one occured during
the
preprocessing:
1. laura replied that she thinks, while performing "realign & unwarp"
there
is no need to integrate the covariate motion into the first level model.
is
this right?
2. due to our paradigm, we are forced to design our blocks as separate
sessions. in realignment i got one rp_motion.txt file (in which the
motion
regressors are written) per session. now my question is, how can i
integrate n motion regressors into my first level model?
is it appropriate to build one rp_.txt file out of the x files by
attaching
the single files into one? so i would be able to integrate only one
motion
covariate file into the model.
thanks
markus
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