Something environmental? Did you all teach at the same location for an extended period perhaps or live near eachother under power lines?
Yes, we all instructed on the same simulators. Two of us shared the same office and the 3rd was in an office next door but one.
I did ask the consultant if it could electro magnetic radiation from the consoles, or even wearing headsets for years. He said that it is not a brain problem but a problem with the immune system. Sonething must kick it off but nobody knows what.