I am not sure, what do you mean by "to reconstruct amplitudes", but one possible issue I can think of is if you contrast betas from time modulator and "standard"/trial regressor e.g. to ask whether time effect is larger than main effect of trials...
Vale,
Auer, Tibor M.D. Ph.D.
MRC Cognition and Brain Sciences Unit
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-----Original Message-----
From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]] On Behalf Of H. Nebl
Sent: Tuesday, March 10, 2015 2:10 PM
To: [log in to unmask]
Subject: Re: [SPM] Time modulation
> but only the scaling of the regressor and still corresponds to a linear time effect
Sorry to bother you, but if it's a scaling issue, then this should affect results when combining the beta estimates from the standard regressor and the time modulator to reconstruct amplitudes for certain time points, shouldn't it?
Best,
Helmut
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