Dear experts, Apologies for asking this question again. When I extract values for a group difference map (structural MRI) in spm2, what exactly are the vaues I obtain for each subject, e.g. the eigenvalues. Could you direct me to a reference that explains this ? Yours, Chiara Nosarti __________________________________ Chiara Nosarti PhD, Division of Psychological Medicine, Room M5.01.05 Section of General Psychiatry, PO Box 63, Institute of Psychiatry 16 De Crespigny Park, Denmark Hill, London SE5 8AF, UK Tel: 0207 848 0133 Fax: 0207 701 9044