coordinate mismatch in ASA headmodel and *.nii -files

[Gregor Volberg]

Dear fieldtrippers,

thanks a lot for the helfulp comments on my former source analysis questions. This one is maybe not directly related to fieldtrip's source analysis functions:
I use individual headmodels generated by ASA software (which reads and segments MRI images in Siemens DICOM format) for source reconstruction. The corresponding anatomical data is in an *nii-file, generated with the DICOM-import function if SPM5. Now, when I plot the individual functional data overlayed on the individual anatomical data, it seems that X and Y coordinates are exchanged, Y ist rotated by 90 or -90 degrees, and Z is shifted into positive direction for functional compared to structural data. I tried to normalize the volume data with ft_volumenormalise using the individual MRI as template file, but this warps both functional and anatomical data so that the mismatch between both is still there. 

Did some ASA-user have a similar problem - is there maybe a necessary transformation  that I have overlooked? Thanks again in advance -
Gregor



-- 
Dr. rer. nat. Gregor Volberg <gregor.volberg at psychologie.uni-regensburg.de> ( mailto:gregor.volberg at psychologie.uni-regensburg.de )
University of Regensburg
Institute for Experimental Psychology
93040 Regensburg, Germany
Tel: +49 941 943 3862 
Fax: +49 941 943 3233
http://www.psychologie.uni-regensburg.de/Greenlee/team/volberg/volberg.html
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