[FieldTrip] MNI template warping to fit the electrode locations

[IMALI THANUJA HETTIARACHCHI]

Dear Fieldtrippers,

I use a MNI template as the volume conduction model (vol) as I have no individual MRI files. However I have the electrode locations of the subject.

I read my sensor locations with
elec = ft_read_sens('sensor_file')
and then use
[vol_coreg, sens] = ft_prepare_vol_sens(vol, elec)
For coregistration of electrodes.

When I plot the outer boundary with my sensors it looks as in head.jpg attached image. Shown in blue are the electrode locations of the original file.

It seems that the electrodes are shifted upwards , say FP1 for instance is way above the forehead.

Is there anything I can do to warp the MNI template volume(vol) to the original electrode locations(shown in blue)? Or am I doing something conceptually wrong here?

Can you please tell me what is the correct thing to do with fieldTrip when only electrode location file is available?

Many thanks in advance

Kind regards
Imali


Imali Thanuja Hettiarachchi
PhD Candidate
Centre for Intelligent Systems research
Deakin University, Geelong 3217, Australia.

Mobile : +61430321972
Email: ith at deakin.edu.au<mailto:ith at deakin.edu.au>
www.deakin.edu.au/cisr<http://www.deakin.edu.au/cisr>

[Description: Description: Description: cid:1216BE20-1800-4A47-8B9F-E7B9D94831CD at deakin.edu.au]




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