Subject: | | Re: parametric modulation centering |
From: | | Colin Hawco <[log in to unmask]> |
Reply-To: | | [log in to unmask][log in to unmask]> wrote: > Dear SPM experts, > > I've seen a couple postings about the reporting of peak vs cluster-level results, but only for imaging studies. If I'm only interested in analyzing time-frequency images, can I report both, or should I stick to one level? Also, what happens with cases where I obtain a significant cluster but no significant peak, is that meaningful/reportable? And lastly, does obtaining an extent threshold (e.g. as in https://github.com/CyclotronResearchCentre/SPM_ClusterSizeThreshold) make sense for this kind of data? > > Thank you very much, > [log in to unmask] |
Date: | | Sat, 16 Apr 2016 17:24:57 -0400 |
Content-Type: | | text/plain |
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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
[log in to unmask]
-----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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