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Dear BUCNI users, I am writing to let you know of an issue I encountered while scanning today and that I wouldn't have spotted if Oliver didn't come in during the scan. I hope this will be useful for other operators as well. When you are collecting functional data using an EPI sequence, usually the direction of phase-encoding is front-to-back. The direction of phase-encoding is the one in which you have basically all of your EPI artifacts, so ideally you want to be in control of where they are... If you need to tilt your field of view massively on the horizontal plane, i.e. >=45°, the scanner will automatically, without warning, change the phase-encoding to left-to-right (apparently the scanner here is trying to be helpful and avoid massive wrap-around artifacts that you would have if scanning in the head-foot, i.e. vertical or close to vertical, direction). In most of the cases, you don't want left-to-right phase-encoding because this will introduce distortions on the left-right direction and you might end up with hemispheric asymmetries in your data that are caused by the phase-encoding artifacts. While you are acquiring the data, you can see that the distortions and the noise outside of the brain are now on the x-axis (btw, there is an arrow on the field of view box that shows you the direction of phase-encoding). So, the cause of this is the change of the phase-encoding direction that you can fix by either using a smaller tilt or manually changing the phase-encoding direction to front-to-back and checking that the field of view is well positioned to avoid wrap-around artifacts. I hope this helps. Cheers, Elisa To leave the list, go to http://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=bucni&A=1.