ABSTRACT
A common idiom now, the idea that one would need another hole in the head was once a valid concern. Fossil records showing signs of holes bored in human craniums have been found spanning as far back as 7000 years, and in many widespread regions like Peru, China, Africa, and Europe. Signs of bone healing further indicates that these individuals were alive at the time of trephination (or trepanning). Attempts to identify an explanation for a seemingly global phenomenon have suggested spiritual remedies for mental illness, such as allowing demons to escape the head through the newly opened window, as well as medical intervention, such as to relieve the intracranial pressure that contributed to headaches and other physical illnesses. While some sub-cultures practice ritualistic or self-trephination, the craniotomy has primarily taken its place in modern medicine, and is only used in cases of absolute necessity. Lending some validity to the historical records, craniotomies are now known to relieve intracranial pressure in cases of swelling, greatly reducing severity of damage to the brain. In experimental settings, craniotomies or ‘bone windows’ are kept to the minimum size necessary to allow access to the brains of rats and mice for manipulation while maintaining experimental control. Examination of modern craniotomies further allow us to study bone healing, as well as physiological and psychological effects of the procedure, potentially giving us newer explanations for why such a method was so commonly practiced across the world and for such an extensive span of time.
