Migraine treatment
Ever experienced that pulsing sensation trapped in your head and you felt like you wanna rip the top of your head off? To give it space? I do.
In those days, they probably thought it was a spirit trapped in the head.
Yeah I can imagine the surgery working.
I don't think it was treatment for mental illness, it was unheard of. Cos magic mushrooms and stuff would ironically give you what looked like mental illness, so they looked upon it as good.
Mental illness meant you were communicating with spirits.