Dear SPMers,
I have recently collected event-related data on an executive function task
over 6 sessions (or runs). The paradigm is such that there are many error
trials. Occasionally a participant has no correct trials for a given
condition in a session, hence SPM multi-session analyses are confounded.
I do not know what to do except simply exclude those sessions where this
occurs (it is rare), but I want to avoid losing SNR. I thought that
proportionally scaling the data volume-wise first, then modelling as a
single session might be OK. Can anyone advise me?
Thankyou,
Matthew.
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