Dear Graham:
The SPM template brains are based on the NIH-P20 project PI- John Mazziotta,
and are often cited as the ICBM template brain (icbm = international
consortium for brain mapping). They approximate Talairach space in the sense
that they are based on the same landmarks and orientation but as you notice
the brain is bigger than the original talairach atlas brain and is stretched
in some places.
I find that one can use the talairach atlas as a very rough guide to
location. However, for better localization I find it best to refer to the
atlas by Duvernoy which provides sections of the brain in the three
orthogonal orientations (not normalized but nonetheless useful).
regards,
Darren
> Dear Graham,
>
> > I notice that the documentation describes the template images supplied with
> > SPM as, approximate to the space described in the atlas of Talairach and
> > Tournoux (1988). I was just wondering how 'approximate' they are and
> > whether or not the co-ordinates provided by SPM should be reported as being
> > 'Talairach'. For example, we are interested in the fusiform gyrus and it
> > seems to me that the co-ordinates provided by SPM are about 2-4mm inferior
> > compared to the Talairach atlas.
>
> Matthew Brett has posted a helpful discussion of MNI/Talairach differences
> at http://www.mrc-cbu.cam.ac.uk/Imaging/mnispace.html that I think will
> answer your queries. The bottom line in terms of reporting is to reference
> activation loci to the surface anatomy of that individual subject if in
> doubt.
>
> > Another (unrelated) question: Is it possible to specify a voxel size for
> > reslicing. I know this can done via the default button for spatial
> > normalisation. I would like to be able to coregister a T1 with the mean
> > epi and then reslice while maintaining the original voxel size of the T1.
>
> If you change the voxel size in this way I believe that the voxel size for
> coreg/reslice will also be changed, allowing you to reslice at the smaller
> voxel size.
>
> best wishes,
>
> Geraint
> --
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Darren R. Gitelman, M.D. E-mail: [log in to unmask]
Cognitive Neurology and Voice: (312) 908-9023
the Alzheimer's Disease Center Fax: (312) 908-8789
WWW: http://www.brain.nwu.edu
Northwestern Univ., 320 E. Superior St., Searle 11-470, Chicago, IL 60611
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