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Trepanation, which is also known as trephining, trephinning, or trepanning, refers to the surgical practice of removing a small piece of bone from the skull, generally to relieve pressure on the brain. Techniques of trephinning in pre-Columbian Mesoamerica were identical to techniques practiced in the eastern hemisphere.
Trephinning involves drilling a hole into a human skull using any of several techniques. If the operation is successful, the bone begins to grow back, beginning at the rims of the hole and growing toward the center of the hole. The new bone growth is shallower than the bone at the rim, enabling scientists to determine whether a person survived after the operation. Trephinning appears to have been a truly global phenomenon, found in populations around the world dating as far back as Neolithic times.
Looks like it's been around for a long time!