I am preprocessing my data and have realigned & unwarped via field-maps. I am noticing that a small number of my subjects show what looks like 1 or 2 missing slices from the superior/posterior section of the parietal cortex. This is present in both the mean EPI and first EPI image when I unwarp this way. It is not present in the raw data (1st image) nor in the mean EPI if I just realign (estimate and reslice, without field maps), so I am confident it is field-map related.
Do people know whether this is sometimes a consequence of correcting for field inhomogeneities, or is it indicative of an error I have made?
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