The claim that migraine pain increases with exposure to light, has been backed up by research from Harvard University.
Led by Dr Rami Burstein, the study looked at the part of the brain known as the thalamus which, it was discovered, processes both pain and light.
The photoreceptors in the thalamus mean that the neural pathways for light and pain sensitivity are able to converge and thus increase the pain felt by a patient.
Scientists made the connection when they realised that blind patients experienced the same symptoms unless their optic nerve was damaged, as this was critical to photophobia - a susceptibility to sensitivity to light.
Dr Burstein commented: "We identified a new pathway in the brain that originates in the eye and goes to the brain areas where neurons are found that are active during migraine attacks.
"The light can increase the electrical activity in neurons that are active to begin with."
According to the scientist's research, up to 90 per cent of migraine sufferers experience more pain from their migraine when exposed to light.
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