Dear Adolfo,
|I was making a change in the conditions of my experiment so the header file chnaged. After doing that I needed to edit the header file by setting the origin in x,y,z. after doing realignment I was trying to do corregistration and this error message came: " There is not enough overlap in the images to obtain a solution please check that your header information is ok" , spm_offsub3. I tried also without doing the header edit in spm and the same error message came. Could you please tell me if possible what should I do?. Thank you very much in advance.
The coregistration algorithm will try and make a first pass guess at where
the each of the target and object images are by taking into account where
the origins are set in the respective headers. If you take a look at the
origin in the images you are trying to coregister you will probably find
that they are not very close at all (relative to the anatomical landmarks
on each image). This may be why the algorithm is failing to converge.
If this is the problem, then the solution is to manually edit the header
of the (I presume it's a structural) image you are trying to
coregister to the realigned functionals. Set the origin to roughly the
same location in the structural image as the functional images, then
start the coregistration again. Hopefully
(fingers crossed) this will work. If you also change the header in the
realigned functionals, make sure (of course) that the change is applied to
all the realigned functional scans.
best wishes,
Geraint
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Dr. Geraint Rees
Wellcome Advanced Fellow Lecturer
California Institute of Technology Institute of Neurology
Division of Biology 139-74 University College London
Pasadena 12 Queen Square
California 91125 London WC1N 3BG
voice (626) 395-2880 voice (171) 833-7472
fax (626) 796-8876 fax (171) 813-1420
http://www.klab.caltech.edu/~geraint [log in to unmask]
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