- Headaches are a type of pain referred to the surface of the head from deep head structures.
- The brain tissues themselves are almost totally insensitive to pain.
- Tugging on the venous sinuses around the brain, damaging the tentorium, or stretching the dura at the base of the brain can cause intense pain that is recognized as headache.
- Also, almost any type of traumatizing, crushing, or stretching stimulus to the blood vessels of the meninges can cause headache.
- An especially sensitive structure is the middle meningeal artery, and neurosurgeons are careful to anesthize this artery specifically when performing brain operations under local anesthesia.