I have started to notice over several event-related fMRI studies I am
finding significant deactivation in the ventricles compared with
task. I don't think it's motion: motion parameters were often
regressed out, and it's not just the rim of the ventricles, sometimes
it's even strongest in the center. Also I don't ever have motion
artifact around the outer border of the brain.
I tend to dismiss anything in the ventricles as artifact, but what
exactly kind of artifact is this, or am I actually seeing reliable
signal decreases in the CSF?
Jonas
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Jonas Kaplan, Ph.D.
Research Assistant Professor
Brain & Creativity Institute
University of Southern California
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