Dear Kalina and Russ,
A comment on recent emails on anatomical issues...
Kalina Christoff wrote:
> I'm sorry to be joining this discussion a bit late. I absolutely
> agree that there are many problems in trying to relate the MNI to the
> Talairach space. As Matthew pointed out, however, "embracing MNI space"
> would mean giving up on the idea of localizing activations in terms of
> Brodmann areas.
This would be true if there were no way of harmonising MNI space and
regionally specific cytoarchetecture. However, work is in progress that
is characterising the cytoarchetecture of several human brains (e.g.
from the Zilles lab in Duesseldorf). Crucially for the imaging
community, data from individual brains will normalised into a common
space to form probablistic maps. While these maps will not allow us to
localise activations to specific cytoarcetectonic regions in
individuals, they will allow us to estimate the probability that
activations lie in given cytoarcetectonic areas. This would only be
possible if these probablistic maps were transformed into MNI space, and
I am not aware that this has been achieved yet.
My view is that the use of such maps would circumvent some of the the
problems associated with the inaccuracies of the Talairach atlas and the
algorithms used to convert Talairach and MNI coordinates. I would be
very interested to know how useful other imagers would find such
probablistic data.
Best wishes,
Narender Ramnani
********************************************************************
Dr Narender Ramnani
Sensorimotor Control Group
Department of Physiology
University of Oxford
Parks Road
Oxford OX1 3TP
Oxford University Centre for
Functional Magnetic Resonance Imaging of the Brain,
John Radcliffe Hospital,
Headington,
Oxford OX3 9DU
Tel. 01865 222704 (Direct)
01865 222729 (Admin)
mob. 0771 2632785
Fax. 01865 222717
email [log in to unmask]
*******************************************************************
|