This is a hard problem because it is very easy to pick up differences
between subjects that may be correlated with motion in a subject-wise
manner, but not caused by motion. For example, subjects who move may also
have more physiological global signal from respiratory variations. People
who move may also be more likely to have fallen asleep, which changes
neural activity and connectivity dramatically. Also, motion itself will
cause differences in neural activity (of the same sort that you would see
in a motor task).
In HCP-Style data ICA+FIX does a good job of removing the MR Physics
related artifacts from motion, but it does not address global
physiological noise or any of these other considerations.
Peace,
Matt.
On 6/21/17, 8:10 AM, "FSL - FMRIB's Software Library on behalf of Kathryn
Cullen" <[log in to unmask] on behalf of [log in to unmask]> wrote:
>Dear Anderson,
>Thank you so much for your reply. I was wondering how you might recommend
>what would be the best way to evaluate whether there is still significant
>motion-related variability after FIX is complete, to make the decision
>about whether to include motion confounds.
>Thanks, Katie
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