Dear Lily,
The default channel locations are stored in EEGtemplates subbdirectory
in SPM in *.sfp files. You can find there the biosemi64.sfp file.
However, if the layout is wrong it also means that the 3D channel
locations are wrong for your cap. So the solution would be to either
find or measure channel locations for your layout and fiducials in the
same coordinate system, create an sfp file such as those in
EEGtemplates (just don't put the 'spm' prefix in front of your
fiducial labels) and follow the procedure for loading and
coregistering individual channel locations that is described in the
manual.
Vladimir
On 22 Aug 2013, at 17:04, Lily You wrote:
> Dear SPMers,
>
> We wish to use SPM8 for EEG source reconstruction. However, we have
> a Biosemi 96-channel system and when EEGLAB data are converted to
> SPM8, SPM8 assigns to it a default channel layout of Biosemi 64-
> channel instead. While we can edit the channel layout, we have no
> idea about the coordinates of the fiducials for later steps of
> source reconstruction. Since SPM carries with it default information
> about Biosemi and corresponding fiducials, is there a way we can
> find out the fiducials for our system? Or any pointers for external
> resources? We appreciate the help very much.
>
> Thanks,
> Lily
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