Research shows that unnatural patterns, stripes and contrasts in some paintings are uncomfortable to view, and can literally be a pain. Professor Arnold Wilkins, who led the research at Essex University, says: “We have shown for the first time that the discomfort from looking at complex images like paintings can be predicted, and our test could be used to avoid putting stressful images in public places where they could cause problems for some people.”
This is so true. When people wear striped shirts it makes me dizzy because my eyes waver on the pattern making all warpy. That is the case with any complex patterns or contrasting patterns.
Study volunteers were asked to rate a number of paintings using a seven-point scale for both artistic merit and visual comfort, and the images were then analysed. This showed revealed factors unique to the uncomfortable images. In particular, there were strong contrasts between light and dark, combined at specific points where vision is most sensitive. Simple patterns of stripes with a specific spatial frequency induce headaches.
The researchers then developed computer software primed with the features they detected. They took images of works, analysed them with the software, and found that they were able to predict which would be the most uncomfortable to view. The more unnatural the structure of the paintings, the greater the discomfort.
Just why these images are uncomfortable isn’t clear. One theory is that the brain has evolved to process natural images rapidly, and that it is confused or disturbed by some unnatural patterns. That results in a feeling of discomfort that can trigger headaches, migraines or epileptic seizures in people vulnerable to such attacks.
The researchers also compared photographic images of urban and rural scenes and found that the latter caused less discomfort, possibly because urban areas have more man-made structures with more unnatural patterns. The finding could explain other visual triggers, such as flickering and bright lights.
Wilkins and his team have looked at other stimuli and found the same kind of effects in photographs, typefaces and other images. One of the most uncomfortable images of all, they say, was found to be the lines on the treads on the London Underground escalators.
However, the research is not conclusive. “There is a huge number of myths and old wives’ tales, and a huge amount that is still not known which helps to allow people to have those myths,” says Dr Andrew Dowson, the chairman of Migraine Action’s medical advisory board and head of headache services at King’s College Hospital, London. “Is it, for example, a myth or a truth that food always causes migraine? A study in the US found that chocolate made no difference at all to migraine. It may be that people in the early stages crave and eat convenience foods such as chocolate and cheese. So it may be part of the migraine to want to eat those things rather than that they actually cause it.”
He adds: “Many have realised that the sensory system is ‘sensitised’ within, and also often between, attacks. It has proved more difficult to confirm the suspicion that red and blue wavelengths of light, for example, are actual triggers, and I guess this work is of a similar nature. It would be interesting to see if exposure to one type of image had a different resultant migraine rate, but it is hard to design such a study.”