People who suffer from migraines have differently structured brains. According to new research, those who suffer from the severe headaches (often accompanied by nausea and "aura" - patterns of lights dancing before the eyes) have a thickening in the region of the brain that processes sensory information.
A study of 24 volunteers, 12 of whom suffered from migraine, found that in sufferers, the somatosensory cortex was 21 per cent thicker. It is not yet clear whether the structural anomaly causes the migraine, or if it is somehow caused by the blinding headaches, but the discovery suggests that migraine sufferers could be more sensitive to other pain as well.
The work was led by Dr Nouchine Hadjikhani, based at the Martinos Centre for Biomedical Imaging at Massachusetts General Hospital in Boston, and is published in the journal Neurology.
"Repeated migraine attacks may lead to, or be the result of, these structural changes in the brain," she said.
"Most of these people had been suffering from migraines since childhood, so the long-term overstimulation of the sensory fields in the cortex could explain these changes. It's also possible that people who develop migraines are naturally more sensitive to stimulation."
She says the work is important because it demonstrates that there is a neurological component to migraine attacks. This, she argues, could help explain why migraine sufferers are likely to report other pain disorders: back pain, jaw pain and even sensory disorders such as allodynia, "where the skin becomes so sensitive that even a gentle breeze can be painful".
Although it is a small study, the research has been welcomed by the medical community. Dr Andrew Dowson, medical advisor to the Migraine Action Association, told the BBC: "Who knows where this might lead with new diagnostic possibilities and therapeutic targets?" ®