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Dear all, I am facing a problem in the pre-processing of my fMRI data and wonder if someone has already had this problem and could provide me with some clues as to what the issue might be. Essentially, after the normalisation of my data, I noticed that for some subjects the wu images were distorted with quite a steep angle as seen on the sagital view. On the attached document, the first two scan are from two different subjects for whom I get what I would expect, but the other 5 scans have a much steeper angle despite being accurately registered to the EPI template. Initially I had another 4 subjects for whom the angle and the registration was not great, but after setting the origin on the structural scan to the ac-pc line and co-registering the EPI to the structural scan, it solved the problem and these are now fine. For the other 5 subjects, however, this did not solve the issue. My main concern is that these 5 subjects will influence the final mask for the analyses and lead to a significant reduction in the portion of the brain that will be covered. In any light on this would be greatly appreciated. Thanks in advance. Best, Steph' ------------------------------------------------------------------- Stephane De Brito, PhD Postdoctoral Research Associate Developmental Risk & Resilience Unit Division of Psychology and Language Sciences University College London 26 Bedford Way London WC1H 0AP Tel: +44(0)20 7679 5394 (internal: 25394) <http://www.ucl.ac.uk/clinical-psychology/Research-Groups/DVR/index.htm> http://www.ucl.ac.uk/clinical-psychology/Research-Groups/DVR/index.htm To leave the list, go to http://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=bucni&A=1.