If the brain has no pain receptors, how come you can get a headache?

Question

I've read many years ago in books, that the brain has no nerves on it, and if someone was touching your brain, you couldn't feel a thing.

Just two days before now, I had a very bad migraine, due to a cold. It's become better now, but when I had it I felt my head was going to literally split in half, as the pain was literally coming from my brain.

So it lead me to the question: How come people can get headaches if the brain has no nerves?

Answer 1

Brain, indeed, cannot feel pain, as it lacks pain receptors (nociceptors). However, what you feel when you have a headache is not your brain hurting -- there are plenty of other areas in your head and neck that do have nociceptors which can perceive pain, and they literally cause the headaches.

In especially, many types of headaches are generally thought to have a neurovascular background, and the responsible pain receptors are associated with blood vessels. However, the pathophysiology of migraines and headaches is still poorly understood.

Answer 2

That the brain doesn't have pain receptors has somewhat drifted into the corpus of general knowledge, perpetuated by pamphlets, books and documentaries.
Your question caused me to look up wikipedia. Citing:

A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the pain-sensitive structures around the brain. Nine areas of the head and neck have these pain-sensitive structures, which are the cranium (the periosteum of the skull), muscles, nerves, arteries and veins, subcutaneous tissues, eyes, ears, sinuses and mucous membranes.