I'm not sure what you're asking here. You should be able to see
easily in the FFT if you have such a signal. It's not necessarily
easy to prove that the artefact is linearly added onto everything
else, but if you use MELODIC-based denoising on this single component
and a re-run of MELODIC doesn't show this up again you've probably
done a good job of cleaning it up.
Cheers.
On 10 Jul 2007, at 19:54, Christopher Bell wrote:
> Hello,
>
> I am interested in looking for artefacts similar to this in my
> melodic data.
> How do you determine an artefact like this? More specifically, how
> did you
> determine that the noise was summing linearly on top of the BOLD
> signal? Did
> you attempt to use bandpass filtering prior to using these
> regressors? Thanks
>
> Chris Bell
> University of Minnesota
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