Headaches are telling you something about how your brain works with your body, influencing your behaviour and feelings

We need pain. It seems contradictory to say it, particularly now that we have so many ways of dealing with it and switching it off. Pain not only tells us something is wrong, it also protects us. If you slam the car door on your hand, it’s going to hurt. You will have damaged the soft tissue; all the muscles and ligaments that help you move your fingers. It will no doubt swell up to twice its size. This inflammation is part of the healing process. Your hand feels hot and looks red because of all the extra blood flow. All these inflammatory agents that are acting to heal you are stimulating the pain receptors in your hand, the ones in your skin and your muscles. Your head is not so different except, crucially, the underlying cause can be much more subtle and varied.

As a neuroscientist who writes about headaches, it is somewhat ironic to admit that I suffer from them still. Two recent headaches stand out. The first happened when I couldn’t find my glasses. I’m astigmatic so I see the world on a bit of a slant because my left eyeball is shaped like a rugby ball instead of a football. Just looking around can be effortful. Plus, the search made me late for everything that day which was unpleasant. By the time I got home, my head felt like it was in the grip of giant hands and they had begun to squeeze hard. All I wanted for dinner was a paracetamol sandwich.