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Dear Julie, the coordinates were, are and will be (unless some other template is used) MNI. "Based upon the Talairach system" only means, that the MNI brain is oriented according to the conventions introduced by Talairach - (0,0,0)mm at AC, y axis running through AC-PC, y-z plane at brain midline... Volkmar On Fri, 27 Oct 2006, JULIE E MCENTEE wrote: > I am trying to clarify whether the x, y, z coordinates displayed when clicking 'volume' when the glass brains are displayed on a 'Results' page following the definition of a contrast are Talairach or MNI. The SPM99 manual (I know its an outdated version, but I'm working on old data) states that they are Talairach. However, can you explain the following from the manual regarding MNI: > > o The space of the template images in SPM is based upon the Talairach system, but does > not make assumptions about brain symmetry, and includes the cerebellum. > o The stereotactic space is based on 152 brains from the Montréal Neurological Institute, > and will eventually be replaced in due course by a 450-brain version for the entire ICBM > consortium (). > o The 152 subject average brain was chosen rather than the MNI305 official standard brain > because from the 152 subjects T2- and PD-weighted images were also available, allowing > much more flexibility in the range of different MR contrasts that can be spatially > normalized to the same stereotaxic space. See spm_templates.man for details. > o A combination of templates may be used when the image to determine parameters from is > different (e.g., intensity with a new MRI sequence) from the templates provided by SPM. > For other purposes, e.g. normalising PET-ligand scans, creating a user-specified template > should be considered. > > Please reply to all. > > Much appreciated, > > Julie E. McEntee, M.A. > Senior Research Program Coordinator > Department of Psychiatry- Neuroimaging > Johns Hopkins University School of Medicine > 600 N. Wolfe St./ Phipps 316 > Baltimore, MD 21287 > Phone: 410-502-0468 > Fax: 410-614-3676 > > -- Volkmar Glauche - Department of Neurology [log in to unmask] Universitaetsklinikum Freiburg Phone 49(0)761-270-5331 Breisacher Str. 64 Fax 49(0)761-270-5416 79106 Freiburg http://fbi.uniklinik-freiburg.de/