Hi - lots of discussion of this in the literature over the years…..best to look at that.
We don't do it.
Cheers, Steve.
On 6 Dec 2012, at 16:57, Marcelo Mattar wrote:
Is it a good idea to include a global signal covariate (average signal over all voxels) in your GLM, if you're performing a standard task-fMRI data analysis? What would be some pros and cons?
--Marcelo
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