Hi there,
I am picking up on some old threads that involve the fsl_motion_outliers script to identify and exclude residual motion artifacts. I read that it wouldn't cause any bias if the confound matrix was included even in cases where there is hardly any movement. I ran it on one subject with some degree of movement and it identified 12 outliers (volume has 209 time points) plus some blobs in the resulting zstat images disappeared. So I was wondering if there's a chance to reduce the power by including these confounds. Also how would it account for correlations between movement and activation. And if it is safe to use, why isn't it included in the default routine?
Our subjects appear to move quite a bit so this is really what we'd like to apply as standard procedure if it does more good than harm. What could be the negative consequences?
Thanks,
Torsten
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