[MINC-users] motion correction and lid closure

[Marc Schoenwiesner]

Hi,

this is a question about intra-subject intra-modality image registration to
correct motion within a run of functional images. In their 2002 neuroimage
paper Stephan et al. showed that closing and opening the eyes may lead to small
misalignments in the registration, because the intensity of the eye voxels
changes. Some people recommend to mask out the eyes in functional runs before
motion correction. How could this be done with tools at the BIC? Zeroing the
eye voxels in all images may not be the optimal solution, because this creates
an artificial structural feature which might mislead the registration even
more... Roger Woods AIR package for instance has a -mask option which allows to
disregard the eye signal without creating structural features. How could that be
done in the frm_preprocess step?

Thanks for any pointers!
Cheers
Marc