Trepanning

Trepanning is the surgical process of drilling a small hole in the skull to increase blood flow to the brain. Regarded as a pseudoscience, many believe it can elevate consciousness and bring back a childhood state of imagination and perception. About 5-10% of surviving Stone Age skulls have holes in them from trepanning. Needless to say, such exposure of the brain to airborne germs would often be fatal. Even John Lennon tried to convince Paul McCartney to drill a hole in his skull explaining “All you’d have to do is just bore a little hole in your skull and it lets the pressure off.”