forward modelling without anatomical info

[Jan Mathijs Schoffelen]

Dear Tom,

As far as I know, the 'ctf-format' standardised mri does not exist. Creating an anatomically accurate forward model, while the actual anatomical information is lacking, is tricky business. What kind of forward model do you actully use? The multiple sphere model based on the ctf-shape files? If so, you could try to come up with an 'averaged' multipsphere model (thus bypassing the need for a standardised MRI), although this is not trial.  However, I wonder whether this would yield better results than just taking an 'averaged' single sphere model.
I wonder what you mean by your statement that localisation is much more accurate when using ctf-formatted MRIs. Do you  know where your activation should end up then?

The function beamformer_pcc is as far as I know still in its experimental stage and only for use within the FC Donders Centre. However, beamformer_dics shares most of the functionality, but obviously not all of it.

Regards,

Jan-Mathijs

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