we have a rather basic question on how breaks within an event-related fMRI
paradigm (four types of "events") should best be handled.
The final goal of the analysis is to contrast the four different types of
events against each other.
After block-like presentation of the four different, intermingled events,
breaks of 20 seconds are programmed to allow
the subject to rest. Should this "lower" baseline be explicitly modelled in
a block like 5th regressor, or does this just
introduce some collinearity that is not wanted?
Thank you very much for any advice,
Max Planck Institute of Psychiatry
NMR Research Group
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