Dear SPMers,
Could somebody kindly point me to where I can dl/see the structure of
headshape.mat file used during preparation of converted meg file.
Question: After converting my CTF meg files it appears the sensors are
rotated 90 degrees around Z (up-down) axis. I have no digitized data for my
data, and if i understand in SPM I can create headshape.mat and enter the
subjects fiducial coordinates into shape.fid.pnt? I am further guessing that
this preparatory step is what aligns the meg coordinate system with spm/mni
system, which is a necessary condition for creating spm images?
Finally, why is this realignment/coregisteration step not occuring
automatically for meg data that already contains the 3 necessary fiducials
(lt/rt periauriculars and nasion)?
thanks in advance,
Kambiz
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