Trepanning is an ancient (back to Bronze Age) surgical procedure (the earliest attested) that involves cutting a one inch or so circular hole through a person's cranium, to relieve pressure from a brain bleed, or perhaps to vent evil spirits, or for other for other ritual reasons. There’s a substantial body of archeological evidence for the practice,

But I can’t help thinking the patients (subjects?) would have found it tedious. They must have been bored out of their skulls.