Painful stimulation of the forehead increases photophobia in migraine sufferers.

Thresholds for visual and auditory discomfort were investigated in 51 migraine sufferers and 27 controls of similar age and sex distribution who rarely suffered from headache. Tests in migraine sufferers were carried out during the headache-free interval. Discomfort thresholds were measured before and during painful stimulation of the forehead with ice. The visual discomfort threshold was lower in migraine sufferers than in controls, and decreased further during painful stimulation of the forehead. In contrast, the auditory discomfort threshold was similar in migraine sufferers and controls, and did not decrease during painful stimulation of the forehead. These findings suggest that trigeminal discharge contributes to photophobia but not phonophobia in migraine sufferers.