Dear Rahyeong, I am not sure I understand the problem. There seems to be inhomogeneity in your images, but I am not clear whether this is before or after correction. Inhomogeneity correction is part of Unified Segmentation (Ashburner and Friston 2005), which you can access through the SEGMENT button in SPM5 and 8. While setting this up, you can specify that you want the bias- corrected image written out. Once you've run SEGMENT on your images, you can then check the bias- corrected image - with a bit of luck this should reduce the inhomogeneities you see. Hope this helps, Best wishes, Alexander --------------------------------- Alexander Hammers, MD PhD NEW Affiliation: Chair in Functional Neuroimaging Fondation Neurodis http://www.fondation-neurodis.org/ NEW Postal Address: CERMEP – Imagerie du Vivant Hôpital Neurologique Pierre Wertheimer 59 Boulevard Pinel 69003 Lyon France Telephone +33-(0)4-72 68 86 34 Fax +33-(0)4-72 68 86 10 Email [log in to unmask];[log in to unmask] Web (London lab) http://www1.imperial.ac.uk/medicine/people/alexander.hammers.html http://www.csc.mrc.ac.uk/Research/Groups/ECN/Epilepsy/ --------------------------------- Other affiliations: Visiting Reader; Honorary Consultant Neurologist Division of Neuroscience and Mental Health, Faculty of Medicine Imperial College London Room 243, Cyclotron Building Hammersmith Hospital, DuCane Road, London W12 0NN and Honorary Reader in Neurology; Honorary Consultant Neurologist Department of Clinical and Experimental Epilepsy National Hospital for Neurology and Neurosurgery/ Institute of Neurology, UCL 33 Queen Square, London WC1N 3BG On 7 May 2010, at 09:08, Rahyeong Juh wrote: > > ----- Original Message ----- > From: Rahyeong Juh > To: [log in to unmask] > Sent: Friday, May 07, 2010 4:02 PM > Subject: inhomogeneity correction > > Dear SPM experts > > Is there any fix the this inhomogeneity correction? How can I fix > the problem? > Who knows? Thanks > > Best Regards > > Rahyeong > <T1_LYT.jpg><T1_LYT3.jpg>