Dear AFNI users,

A couple of my participants have a wrap-around artefact in their functional scan and I'd like to determine whether or not the brain data are invalidated. Looking at the BOLD signal, stats-, stdev-, and snr-maps is helpful but I don't know if it is ok to use this info in some way.

Is there something like SPM's wrap operation in AFNI? In a prior post, Daniel suggested 3dresample but that was with respect to an anatomical scan. Would this still be a valid option? I'm hesitant to resample or cut/glue slices as a functional scan is probably another beast and the extent of the artefact not as obvious as in an anatomical image (aside from the time course issue).

On the other side, while one poor guy (the most severe) apparently has eyes in the back of his head the artefact seems to not affect the data in the brain (judging by stats-, stdev-, and snr-maps when overlaid on the anatomical) but of course this is my subjective appraisal. Would this suggest to leave the images as they are?

Could wrap-around effects be addressed, at least to some degree, via preprocessing routines (skull-strip the epi+orig, don’t smooth, only normalize/resample at the GLM level) in an effort to contain the issue in space?

What are other labs doing in such circumstances?

Thanks so much for your help in advance!

Nic