Hi all,
I have a question about accounting for motion in the scanner. We scan
many children with ADHD, and they tend to move around, and occasionally
there is a period of about 10 seconds of fidgeting in the middle of a run.
In the past, we have removed these volumes and adjusted the timing files,
but I was wondering - would it work to create a block regressor to cover the
period of motion, and assign it a zero in the model (and remove the events
during that period from the timing file), so that SPM "ignores" the data
from that period? Or would keeping the motion volumes in the model still
affect the results somehow? It would be convenient to use this technique,
because I was also thinking of using the same technique for the infrequent
times when a child falls asleep in the scanner. Does this technique sound
dodgy? Thanks!
Daniel
Daniel Simmonds
Developmental Cognitive Neurology
Kennedy Krieger Institute
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