Hello, I have a few question regarding the coregistration display:
In the co-registration of headpoint data and MRI, I see different colors displayed for different head points.
(see tutorial - Tutorials/ChannelFile - Brainstorm (usc.edu))
Can you please explain what each color represents? I couldn't find this information in the tutorial.
In the above-cited tutorial, I see that "if you ever see the grey head surface intersecting this yellow helmet surface, there is obviously something wrong with the registration". However, if the grey head surface is simply adjacent to the yellow helmet (for example, if the participant is resting his head on the helmet) - is this acceptable? or does it mean that the scan will be too noisy due to the proximity of the head to the sensors?
I assume each MEG manufacturer has a slightly different helmet size. does brainstorm display different helmets for different manufacturers (=sizes)?
Which colors do you mean? As depending on the option they can mean different things.
Please post an screenshot
The tutorial emphasizes that if the surfaces intersect there is something wrong as certainly the participant head was not passing through the helmet. The situation that you describe sounds ok ,it that was the position of the subject.
Yes, the helmet surface is created with the manufacturer information of the distance between helmet and MEG sensors