hi all,
i'm doing human fmri study with stimulation on the subject.
mostly whenever we applied pressure, subjects' head move aroud 0.8 sometimes ~1.8 (mm? voxel? shift parameter in the *.par file from mcflirt-fsl). i know i'd better change the design might not cause much motions, but it'll be critical for me if i change.
probably, the raw data in itself have a distorted slice timing and/or too much motion so that the data will be interpolated alot.
here's my question...
is there any way to use priori information about the movement(shift mostly) so that i can shift each volume without any interpolation before i run mcflirt-fsl, as if the 4D data collected without much motion?
the reason that i'm asking is that i don't want the data to be interploated too much, so it would be better if i can change the initial location before motion correction.
(i've looked through the mcflirt options '-init' but don't know in detail.)
my idea: put some markers on the subject's head during the scan then detect the marker so that i can quantifiy the movement (using mcflirt only based on the marker not the brain) during the run. then shift the each volume using the shift-information from my marker then perform motion correction. but don't know more better way.
thanks in advance,
jeongchan
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