Hi, all. I find that the orientation of output of fslreorient2std is RAS, while the MNI152.. files are in LAS. I wonder whether the LAS or RAS is the 'standard' orientation in FSL. Thanks. Xiang-zhen -- ----------------------------------------------------------------------------------------- Kong Xiangzhen State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China, 100875.