About blue lights and suicide


Red makes the heart beat faster.
You will often find these and other claims made for the effect of different colors on the human mind and body. In addition to such common claims, the physiological mechanisms underlying human color and light perception have been known for some time. But it is only in recent decades that a separate path for the non-visual effects of color has been discovered.

Tokyo’s blue railway stations

Japan is one of the countries with the highest suicide rates in the world. Now it has successfully implemented a package of measures to help with depression, overwork and isolation.

Recent research has found an effect of colored light on heart rate and blood pressure: red light seems to increase the heart rate while blue light lowers it. Based on the claim that blue light could make people less impulsive and calm, blue colored lights were installed at platforms on Tokyo’s railway lines to reduce the incidence of suicide. As a result, the suicide rate in these stations dropped by 74 percent. The success was so significant that psychologists assume it might have really changed people’s minds in a longer term.

Scientific background and pink prisons

On this occasion, experiments were conducted in a three-year study to investigate the influence of blue light on impulsivity. The University of Leeds has specially set up a light laboratory to evaluate the effect of light on human behaviour. It has been proven that red actually makes our heart beat faster and blue calms blood pressure. An Australian study came to the same conclusion.

It is known that the eye performs two functions. Light sensitive cells at the back of the eye send electrochemical signals primarily to an area of the brain known as the visual cortex. In this cortex, the visual images we see are formed. The novelty is that some retinal ganglion cells respond to light by sending signals to the hypothalamus, which plays no part in forming visual images. The hypothalamus responds by forming hormones that regulate our sleep, hunger and body temperature.

So there is a clear mechanism explaining why color and light affect our blood pressure, mood and impulsivity. The head of the study also reports on prisons in Switzerland and America, where prisons significantly reduced the aggressiveness of inmates with bright pink painted walls – the “cool down pink“. Psychologists observed that the inmates calmed down within 15 minutes: “The color has been shown to reduce their physical strength.”

The use of colors

The discovery of the non-visual pathway has given new impetus to research, exploring how we physiologically and psychologically respond to our environment. Although blue light alone does not replace comprehensive suicide prevention in train stations, it can be a small contribution to comprehensive suicide prevention. The assumption that color can affect us in ways that go beyond normal color vision also brings interesting new ways of looking at things, for example in terms of the design of classrooms, packaging, logos, etc…

picture credits: willian justen de vasconcellos via unsplash.com

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About Salome Lixl

..currently I'm studying at the University of Vienna trying to strengthen my abilities and to find my passions. A way to implement this is writing.

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