Here’s why looking at buildings can literally give people headaches

Ouch. A redeveloped Nazi holiday camp (yes, really) in Binz, Germany. Image: Getty.

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 grey 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”.

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.

Hurts to look at

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.

Easier on the eye? Image: Top: Sam Beebe/Flickr/creative commons; bottom: Tsaiian/Flickr/creative commons.

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.

They don’t make ‘em like they used to. Image: jonjk/creative commons.

We then analysed 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 colour. 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.

Better out than in. Image: vincentq/Flickr/creative commons.

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.


The ConversationPerhaps 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.

Arnold J Wilkins is professor of psychology at the University of Essex.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

Was the decline in Liverpool’s historic population really that unusual?

A view of Liverpool from Birkenhead. Image: Getty.

It is often reported that Liverpool’s population halved after the 1930s. But is this true? Or is it a myth?

Often, it’s simply assumed that it’s true. The end. Indeed, proud Londoner Lord Adonis – a leading proponent of the Liverpool-bypassing High Speed 2 railway, current chair of the National Infrastructure Commission, and generally a very influential person – stood on the stairs in Liverpool Town Hall in 2011 and said:

“The population of Liverpool has nearly halved in the last 50 years.”

This raises two questions. Firstly, did the population of the City of Liverpool really nearly halve in the 50 year period to 2011? That’s easy to check using this University of Portsmouth website – so I did just that (even though I knew he was wrong anyway). In 2011, the population of the City of Liverpool was 466,415. Fifty years earlier, in 1961, it was 737,637, which equates to a 37 per cent drop. Oops!

In fact, the City of Liverpool’s peak population was recorded in the 1931 Census as 846,302. Its lowest subsequent figure was recorded in the 2001 Census as 439,428 – which represents a 48 per cent decline from the peak population, over a 70 year period.

Compare this to the population figures for the similarly sized City of Manchester. Its peak population also recorded in the 1931 Census as 748,729, and its lowest subsequent figure was also recorded in the 2001 Census, as 392,830. This also represents a 48 per cent decline from the peak population, over the same 70 year period.

So, as can be seen here, Liverpool is not a special case at all. Which makes me wonder why it is often singled out or portrayed as exceptional in this regard, in the media and, indeed, by some badly briefed politicians. Even London has a similar story to tell, and it is told rather well in this recent article by a Londoner, for the Museum of London. (Editor’s note: It’s one of mine.)

This leads me onto the second question: where have all those people gone: London? The Moon? Mars?

Well, it turns out that the answer is bit boring and obvious actually: after World War 2, lots of people moved to the suburbs. You know: cars, commuter trains, slum clearance, the Blitz, all that stuff. In other words, Liverpool is just like many other places: after the war, this country experienced a depopulation bonanza.


So what form did this movement to the suburbs take, as far as Liverpool was concerned? Well, people moved and were moved to the suburbs of Greater Liverpool, in what are now the outer boroughs of the city region: Halton, Knowsley, St Helens, Sefton, Wirral. Others moved further, to Cheshire West & Chester, West Lancashire, Warrington, even nearby North Wales, as previously discussed here.

In common with many cities, indeed, Liverpool City Council actually built and owned large several ‘New Town’ council estates, to which they moved tens of thousands of people to from Liverpool’s inner districts: Winsford in Cheshire West (where comedian John Bishop grew up), Runcorn in Halton (where comedian John Bishop also grew up), Skelmersdale in West Lancashire, Kirkby in Knowsley. There is nothing unique or sinister here about Liverpool (apart from comedian John Bishop). This was common practice across the country – Indeed, it was central government policy – and resulted in about 160,000 people being ‘removed’ from the Liverpool local authority area.

Many other people also moved to the nearby suburbs of Greater Liverpool to private housing – another trend reflected across the country. It’s worth acknowledging, however, that cities across the world are subject to a level of ‘churn’ in population, whereby many people move out and many people move in, over time, too.

So how did those prominent images of derelict streets in the inner-city part of the City of Liverpool local authority area come about? For that, you have to blame the last Labour government’s over-zealous ‘Housing Market Renewal Initiative’ (HMRI) disaster – and the over enthusiastic participation of the then-Lib Dem controlled city council. On the promise of ‘free’ money from central government, the latter removed hundreds of people from their homes with a view to demolishing the Victorian terraces, and building new replacements. Many of these houses, in truth, were already fully modernised, owner-occupied houses within viable and longstanding communities, as can be seen here in Voelas Street, one of the famous Welsh Streets of Liverpool:

Voelas Street before HMRI implementation. Image: WelshStreets.co.uk.

The same picture after HMRI implementation Image: WelshStreets.co.uk. 

Nonetheless: the council bought the houses and ‘tinned them up’ ready for demolition. Then the coalition Conservative/Lib Dem government, elected in 2010, pulled the plug on the scheme. 

Fast forward to 2017 and many of the condemned houses have been renovated, in a process which is still ongoing. These are over-subscribed when they come to market, suggesting that the idea was never appropriate for Liverpool on that scale. 

At any rate, it turns out that the Liverpool metropolitan population is pretty much the same as it was at its peak in 1931 (depending where the local borough boundaries are arbitrarily drawn). It just begs the question: why are well educated and supposedly clever people misrepresenting the Liverpool metropolis, in particular, in this way so often? Surely they aren’t stupid are they?


And why are some people so determined to always isolate the City of Liverpool from its hinterland, while London is always described in terms of its whole urban area? It just confuses and undermines what would otherwise often be worthwhile comparisons and discussions. Or, to put it another way: “never, ever, compare apples with larger urban zones”.

In a recent Channel 4 documentary, for example, the well-known and respected journalist Michael Burke directly compared the forecast population growths, by 2039, of the City of Liverpool single local authority area against that of the combined 33 local authority areas of Greater London: 42,722 versus 2.187,708. I mean, what bizarre point is such an inappropriate comparison even trying to make? It is like comparing the projected growth of a normal sized-person’s head with the projected growth of the whole of an obese person, over a protracted period.

Having said all that, there is an important sensible conversation to be had as to why the populations of the Greater Liverpool metropolis and others haven’t grown as fast as maybe should have been the case, whilst, in recent times, the Greater London population has been burgeoning. But constantly pitching it as some sort of rare local apocalypse helps no one.

Dave Mail has declared himself CityMetric’s Liverpool City Region correspondent. He will be updating us on the brave new world of Liverpool City Region, mostly monthly, in ‘E-mail from Liverpool City Region’ and he is on twitter @davemail2017.