What did Julius Caesar, Gustav Mahler and Sigmund Freud have in common? They all suffered from debilitating migraine headaches.

According to recent studies, 14.7 per cent of Europeans suffer from regular migraine headaches, which consist of an intense throbbing that lasts four or more hours. Britain’s Migraine Trust says more people suffer from migraine than diabetes, asthma and epilepsy combined. And it is expensive: the US spends an estimated $17bn a year treating patients’ migraines.

Yet very little is known about effective treatment of migraines, which are a genetically determined vulnerability of the brain. During a migraine the brain overreacts to a variety of stimuli that can range from hormone cycles to stress or even changes in the weather or diet.