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Hi Kun-Han, this question has been discussed several times. Background is, you either want an externally-generated template that favors no party (patients or controls) or, if you have enough subjects yourself (say, >>100), you should use both patients and controls in order to avoid preferential processing of one group (say, controls). If you have only patients in your sample and enough of them, go ahead with creating a template from them only. Having said that, in newer versions of SPM, customized templates are not really that much of an issue anymore except in very special populations (say, children or elderly adults). Hope this helps, Marko John Lue wrote: > Dear SPMers, > > As I know, spatial normalization algorithm minimizes the residual squared difference between the images being normalized > and the template. In SPM package and most papers, the customized template was created from normal subjects. > Therefore, my question is: > > Why should template be created from normal subjects rather than patients ? > > > Please forgive my ignorance. > > Best wishes and thanks, > > Kun-Han Lue > -- ____________________________________________________ PD Dr. med. Marko Wilke Facharzt für Kinder- und Jugendmedizin Leiter, Experimentelle Pädiatrische Neurobildgebung Universitäts-Kinderklinik Abt. III (Neuropädiatrie) Marko Wilke, MD, PhD Pediatrician Head, Experimental Pediatric Neuroimaging University Children's Hospital Dept. III (Pediatric Neurology) Hoppe-Seyler-Str. 1 D - 72076 Tübingen, Germany Tel. +49 7071 29-83416 Fax +49 7071 29-5473 [log in to unmask] http://www.medizin.uni-tuebingen.de/kinder/epn ____________________________________________________