[FieldTrip] using a four shell model

[Max T.]

Dear all,

I am new to fieldtrip and I currently tried to do a simple dipole fit
on simulated data. I tried to analyse EEG data (33 channels) which was
forward modeled (outside fieldtrip) using a single dipole and a four
shell headmodel with radii of 85mm for the head, 6mm for the scalp,
7mm for the bone and 1mm for the csf. I tried several ideas on how to
transfer this head model into fieldtrip. Unfortunately, none of my
dipole fits inside fieldtrip suited my forward model.

My script looks like this:

  avg = besa2fieldtrip('data.mul');
  avg.elec = ft_read_sens('data_elec.sfp');

  vol.o = [0 0 0];
  vol.r = [0.84 0.85 0.92 1];
  vol.c = [0.3300 1 0.0042 0.3300];

  cfg = [];
  cfg.elec = avg.elec;
  cfg.vol = vol;
  cfg.gridsearch = 'no';
  cfg.model = 'regional';

  dipol = ft_dipolefitting(cfg,avg);

I would appreciate any help with this.

Max Taubert