I was wondering if anyone would care to comment on a method for dealing
with isolated bad volumes in data. An example would be a volume that's
rendered unusable because of movement during the volume. (Leads to
alternating slice brightness.)
One cannot merely discard the entire timepoint, because that would lead to
a discontinuity in the time series.
For the statistics itself, I add a "user-specified" regressor singling out
that individual timepoint, to "regress out" the effects of that volume.
At the preprocessing stage, the volume must be replaced if slice timing
correction is used, else the data corruption will "spread" in time.
Currently I merely replace the volume with the average of the neighboring
volumes.
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