Dear SPMers,
I have a question regarding "activations" in the CSF. I have run a simple
event-related design with 3 different conditions which were presented in
random order. Preprocessing, 1st level analyses, and a RFX 2nd level
analysis were done with SPM5.
Looking at some basic main effects on the 2nd level I noticed activations in
the ventricles. The first 5 volumes have been discarded for analysis. Thus,
CSF activations are not likely due to T1 saturation artefacts (if I have
understood previous comments on the helpline correctly...).
Does anybody have an alternative idea how to explain, or even better, to get
rid of these unlovely "activations"?
Thanks and all the best
Gregor
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Gregor Domes
Clinical Psychology and Psychobiology
University of Zurich
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