I am also interested in what criteria people use for removing MELODIC
components that appear to be motion or scanner artefacts. So far, we have
used the following criteria for raters to identify components to omit.
Omit the component if one or more of the following three things is true:
1. One slice has 90% or more voxels activated/deactivated (orange/blue in
the image) and an adjacent slice has less than 30%.
2. If one or more slices has a clear ring around it, with full coverage of
the edge of the brain and little coverage inside the ring. If there is not
100% coverage of the edge of the brain, don’t bother excluding that component.
3. If there is a large spike in the timecourse that is at least 4 units (on
the y axis) more extreme than the next largest spike (or if there are a
couple of large spikes, use the largest spike for comparison and ignore the
next largest one).
If uncertain about #1 or #2, check the time course to see if there are also
large spikes.
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