[Neuroimaging] temporal filtering and confounds when loading with nilearn niftimasker

[Christophe Pallier]

Hello all,

I was wondering if the confounds passed to Niftimasker were detrented
and temporally filtered by the masker.

Looking at the code of nilearn.signal.clean, I see that there are
detrended but not filtered.

Would it not be useful to also filter them before projecting the
signal of the orthogonal of the confounds spaces?

While writing this, I realize that, maybe,  this would have strickly
no effect (for example if filtering and projection operation commute;
sorry if this is obvious...)

(real life case: I extracted timecourse from CSF to include as a
confound before running a func. connectivity analysis, and there are
some low freq in the signal that will probably not be cleaned by
detrending, but differ from voxels in grey matter)

--
Christophe Pallier <christophe at pallier.org>
http://www.unicog.org
http://ww.pallier.org
Tel: +33 (0) 1 69 08 79 34