Yes, I have made a load_label from the right hemisphere and it corresponds to the position were I draw it. I send you another label just in case the other label was corrupted. 
 
Related to the MNI atlas, I have transformed the MNI coordinates into Talairach coordinates using a mni2tal funcion from http://imaging.mrc-cbu.cam.ac.uk/imaging/MniTalairach and then I have used a program from www.talairach.org to obtain the name of the parcel.
 
thank you again for your help,
yolanda

2011/5/4 Douglas N Greve <greve@nmr.mgh.harvard.edu>

There's something strange going on. Did your label come from the right hemisphere? The first coordinate of all the points is negative, indicating that it is on the left side. Which MNI atlas are you using?

doug

7705  -36.725  5.727  20.658 0.000000


Yolanda Vives wrote:
I am using the coordinates obtained with the matlab function "read_label()". I send you one of my labels.
 Thanks a lot,
Yolanda

2011/5/3 Douglas N Greve <greve@nmr.mgh.harvard.edu <mailto:greve@nmr.mgh.harvard.edu>>

   Which coordinates are you using? Can you send me the label?
   doug

   Yolanda Vives wrote:

       Hi Doug,

       The problem is that when I put the coordinates in a MNI altas,
       it says that they correspond to the caudate and not to the
       cingulate and I would like to know if the procedure that I am
       following is correct.

       Regards,
       Yolanda

       2011/5/3 Douglas N Greve <greve@nmr.mgh.harvard.edu
       <mailto:greve@nmr.mgh.harvard.edu>
       <mailto:greve@nmr.mgh.harvard.edu
       <mailto:greve@nmr.mgh.harvard.edu>>>


          Hi Yolanda, they should already be in mni305 coordinates,
       so the
          identity matrix is correct. Did you find a potential problem?
          doug

          Yolanda Vives wrote:

              Hi all,
               I am interested in obtaining the MNI or talairach
       coordinates
              of a label. The procedure that I have performed is the
       following:
               First of all I have performed a QDEC analysis. From the
              results, I have drawn a label of a significant area of the
              brain, that corresponds to the cingulate. Afterwards, I
       have
              used the matlab function read_label to obtain the RAS
              coordinates of this label. To transform these
       coordinates into
              mni coordinates, I have read that  if v = [R A S 1]' and X
              matrix is the matrix from talairach.xfm, then vMNI = X*v
               Taking this into account, I have used the X matrix
       from the
              talairach.xfm of "fsaverage" (where the results of qdec are
              mapped). This matrix is
               1.0 0.0 0.0 0.0
              0.0 1.0 0.0 0.0
              0.0 0.0 1.0 0.0
              so vMNI is the same as v. When I introduce v (or vMNI)
              coordinates into a MNI atlas, I don't obtain the cingulate.

              Could you please help me with this procedure?
               Thank you in advance,
              Yolanda
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   --     Douglas N. Greve, Ph.D.
   MGH-NMR Center

--
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MGH-NMR Center
greve@nmr.mgh.harvard.edu
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Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting
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--
Yolanda Vives
PIC (Port d'Informació Científica)
Campus UAB, Edificio D
E-08193 Bellaterra, Barcelona
Telf. +34 93 586 8232
http://www.pic.es
Avis - Aviso - Legal Notice: http://www.ifae.es/legal.html