Looking at buildings can actually give people headaches. Here’s why

Editor’s Note: Arnold J Wilkins is a professor of psychology at the University of Essex. The views expressed in this commentary are solely those of the writer.

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It’s three o’clock. You’re at work, struggling to focus during the afternoon lull. You gaze out of your office window, hoping for some relief, but instead you feel a headache coming on.

Flat gray concrete lines the streets, while windows form repetitive glassy intervals in stark brick walls. With monotonous straight lines as far as the eye can see, there’s nowhere pleasant to rest your gaze. It may seem a superficial problem, but our research has found that looking at urban landscapes may actually give you a headache.

Over tens of thousands of years, the human brain evolved to effectively process scenes from the natural world. But the urban jungle poses a greater challenge for the brain, because of the repetitive patterns it contains.

Mathematician Jean-Baptiste Joseph Fourier showed that we can think of scenes as being made up of striped patterns, of different sizes, orientations and positions, all added together. These patterns are called Fourier components.

Hard to look at

In nature, as a general rule, components with low spatial frequency (large stripes) have a high contrast and components with high frequency (small stripes) have a lower contrast. We can call this simple relationship between spatial frequency and contrast a “rule of nature.” Put simply, scenes from nature have stripes that tend to cancel each other out, so that when added together no stripes appear in the image.

But this is not the case with scenes from the urban environment. Urban scenes break the rule of nature: they tend to feature regular, repetitive patterns, due to the common use of design features such as windows, staircases and railings. Regular patterns of this kind are rarely found in nature.

Because the repetitive patterns of urban architecture break the rule of nature, it is more difficult for the human brain to process them efficiently. And because urban landscapes are not as easy to process, they are less comfortable to look at. Some patterns, such as the stripes on door mats, carpets and escalator stair treads can trigger headaches and even epileptic seizures.

We came to these conclusions by measuring the efficiency with which the brain processes images of natural and urban scenes. There are two ways of measuring efficiency; the first is to build simple computer models of the way that nerve cells compute what we see.

One model was built by Paul Hibbard (University of Essex) and Louise O’Hare (University of Lincoln), and another at the University of St Andrews by Olivier Penacchio and colleagues. Both models show that when the brain processes images that depart from the rule of nature, the activity of the nerve cells is increased, and becomes less sparsely distributed. In other words, such images take more effort for the brain to process.

For our own research, Olivier and I designed a computer program that measures how well images adhere to the rule of nature. After running the program, we found that departure from the rule of nature predicts how uncomfortable people find it to look at any given image – whether it’s an image of a building or a work of art.

We then analyzed images of apartment buildings, and found that over the last 100 years, the design of buildings has been departing further and further from the rule of nature; more and more stripes appear decade by decade, making the buildings less and less comfortable to look at.

O₂ joy

Another way to measure the efficiency of the brain’s visual processes is to measure the amount of oxygen used by the visual part of the brain, located at the back of the head. When the brain uses oxygen, it changes color. We can track these changes by shining infrared light onto the scalp, and measuring the scattered light which bounces back off the brain and through the skull. Typically, oxygen usage is greater when people look at uncomfortable images, such as urban scenes.

We found that the rule of nature not only predicts the levels of discomfort suggested by computer models, it also predicts how much oxygen is used by the brain. That is, our brains use more oxygen when we look at scenes which depart from the rule. Since headaches tend to be associated with excess oxygen usage, this may explain why some designs give us headaches.

People who get migraines are particularly susceptible to the discomfort from repetitive patterns; these patterns increase the use of oxygen (which in those who sufferer migraines is already abnormally high.) The patterns can give rise to a headache, possibly as a result. Indeed, some individuals with migraine cannot function in certain modern offices, because the patterns bring on a headache every time they enter the building.

Courtesy of Romain Jacquet-Lagrèze

City dwellers are perhaps more acquainted with the architecture of their phones than the skyscrapers that carve out their commutes. However, Hong Kong-based photographer Romain Jacquet-Lagrѐze reckons eyes should be diverted upward. Documenting the colossal sky-rises that crowd the city, Jacquet-Lagrѐze captures these giants from the ground up in his book Vertical Horizons, unveiling extraordinary sights often missed when heads are kept down.

By Monique Todd, for CNN

Courtesy of Romain Jacquet-Lagrèze

A French native with a global trail, Jacquet-Lagrѐze has worked across many major cities as a graphic artist and photographer, but says that Hong Kong was the first metropolis to spark his skyscraper obsession. "I'm used to big cities, Tokyo is very dense and huge but less impressive in terms of height -- it's much more spread out. Hong Kong is more striking in that sense."

Courtedy of Romain Jacquet-Lagrèze

A desire to document unexpected perspectives followed his decision to settle in the city four years ago. Capturing towers of glass and concrete from a point of view that firmly grounds the viewer, Jacquet-Lagrѐze was keen to uncover an otherworldly landscape. "Whenever we are caught in our daily life, we just go from point A to point B, we tend to ignore what's around us. But I find that above us there are plenty of details to look at, [these high-rises] are like streets going up vertically ... it just so happens that you have to use elevators to move through them."

Courtesy of Romain Jacquet-Lagrèze

Working around a grueling schedule, Jacquet-Lagrѐze became acquainted with early mornings and late nights in order to avoid back-lighting when taking the photos. "I tend to prefer the days that are cloudy. In Hong Kong you have clouds that are very low and the light of the city reflects on the clouds."

Courtesy of Romain Jacquet-Lagrèze

Whether they be the towers of finance or low-cost residencies, Jacquet-Lagrѐze appreciates how high-rises evoke a similar sense of grandeur, an allure that mirrors the fast moving life of a booming city. "There is a glamorous aspect ... but in residential areas, I think the glamor is hard to get. If you look at the detail though, no single flat looks the same. The glamor is in the variety."

Courtesy of Romain Jacquet-Lagrèze

With new skyscrapers sprouting up on neglected sites and uncultivated land, nature is rapidly retreating to the city's periphery, leaving a hub filled with shades of silver and gray -- but not much greenery. As Jacquet-Lagrѐze says: "There isn't enough space for nature here."

Courtesy of Romain Jacquet-Lagrèze

Nature, however, finds its way into the shots, with small pockets of sky centering the photos, alluding to an omnipresence that illuminates and enlivens ... even as it's being pushed out.

Courtesy of Romain Jacquet-Lagrèze

Nature isn't the only thing battling for ground in Hong Kong. Traditional structures are also struggling for the limelight amid the encroaching new builds. "Many people here, including myself, are thinking that it will affect the atmosphere of the city, the old style neighborhoods and residential areas will eventually get eaten by the modern high-rise apartment or skyscraper ... it's a little bit worrying."

Courtesy of Romain Jacquet-Lagrèze

Jacquet-Lagrѐze cites the importance of variety, which seems to have reached an equilibrium now, even if a future of constant construction looks to unsettle it. "What I love most about the city now is its diversity and its way of blending together styles that usually don't fit together."

Courtesy of Romain Jacquet-Lagrèze

"One thing that is special about Hong Kong, comparatively with other cities, is that they don't set any limits," says Jacquet-Lagrѐze. "There seems to be a lot of freedom for property developers to build what they want." It's this apparent limitlessness that will continue, he believes, to inspire awe across the world.

Perhaps it’s time for the rule of nature to be incorporated into the software that is used to design buildings and offices. Or interior designers can vary the wall designs, blinds and carpets they install, to avoid adding more stripes indoors.

Of course, some repetitive patterns are an unavoidable result of modular construction. But many stripes are there quite unnecessarily, simply as design features – to catch the eye. Unfortunately, they may end up hitting the head, too.