Her paintings were inspired by her migraine attacks—and they caused pain for others. Curious to understand the relationship, British artist Debbie Ayles approached researchers at Essex University who launched a series of revealing studies into why certain patterns and lights trigger headaches.

“I began, inadvertently at first, to replicate some of the visual auras I experienced,” explained Ayles. “Other migraineurs looking at the work recognized some of the auras within the paintings themselves.” Some complained of actual physical discomfort viewing them.

The first study asked volunteers to rate paintings, some of which had patterns, stripes and contrasts, using a seven-point scale for artistic merit and visual comfort. Those images that were considered uncomfortable had strong contrasts between light and dark, combined at points where human vision is most sensitive. Simple patterns of stripes, which repeat at specific spatial frequencies, can trigger headaches.

While the researchers, who found the same effects in photographs, typefaces and other images, haven’t come to a conclusion as to cause and effect, they theorize that the human brain evolved to process natural images and is confused by unnatural patterns. The resultant feeling of discomfort might trigger migraine, headaches or even epileptic seizures in vulnerable people. The clearest indicator for this theory is that photos of urban scenes caused more discomfort than rural scenes—the most uncomfortable image was of lines on the treads of the London Underground escalators.

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