If you enter a modulator into the GLM, spm will mean center it.
You can confirm this by reviewing the design. The PMs should be centered.
Colin Hawco, PhD
Neuranalysis Consulting
Neuroimaging analysis and consultation
www.neuranalysis.com
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-----Original Message-----
From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]] On Behalf Of Mike
Sent: April-15-16 9:39 PM
To: [log in to unmask]
Subject: [SPM] parametric modulation centering
Hi,
My question is, do we have to mean centering parametric modulation data before entering them in spm? I know that in spm, covariates wlll be mean centered by default. If parametric modulation is just like covariate, it will also be mean centered, but I'm not sure.
Thanks.
Mile
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