Hello all,
I've got two (and a half) questions about fsl_regfilt.
1) When regressing out part of a design matrix, does it matter whether
this design matrix consists only of all possible noise time courses, or
whether it also includes the events of interest? To be more specific, I
want to filter motion related and created a noise only design matrix
that I used for filtering. However, in my study, motion is correlated
with the events of interest. When including the noise regressors in the
design for a feat analysis the influence of the noise gets nicely
reduced, giving more pronounced activation patches. However, I am
concerned that my noise only model would reduce effects, when always
full model will be fitted with fsl_regfilt. So, does fsl_regfilt fit
only the selected regressors, or will the full modell be fitted befor
the selected regressors are filtered out?
2) In the FAQ melodic is suggested for filtering noise related ICs, but
the melodic webpage links to a page, where fsl_regfilt is used. Are this
two options of doing exactly the same thing, or is there a difference?
If they are different, what is the recommended method?
.5) After filtering the data, There is no motion visible when using the
movie loop with fslview. I am pretty impressed by this effect, since I
have data dominated by artefacts. Is fsl_regfilt really that effective
or is this just a bug in fslview causing only one volume being displayed?
Thanks for your help,
wolf
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