Figure 7.4. Head Shape Digitisation

1. In the “Patient Selection” window, click on “Digitise Head Shape”. Click on “Montages” and select “EEG 5 Coils” (double-click pin in top corner to close).
2. Click on “Start”.

The fiducial points or head coil placements are used for head localization (the process of locating the participant's head in co-ordinates which are relative to the magnetometers). They are later used to co-register the MRI Coordinate System with the MEG Head Coordinate System.