I'm trying to create a spherical head model for my MEG dataset, but Brainstorm tells me that the fiducials in my recordings are unmatched with the ones in the default anatomy(ICBM152). I attached here screenshots of registration and the head model using overlapping spheres method. As you can see the CTF helmet is indeed more towards the back of the head, so is the head model. Could this problem be rooted in the process of data collection(hence the polhemus file)? If so, is there any way to fix it?
Thank you very much for your help! I really appreciate it!