When it comes to light, color matters, as Steven Lockley, a neuroscientist at Harvard Medical School (USA), who wanted to find out what happened when a group of subjects was exposed to blue light for 6.5 hours, has been able to verify, comparing it with others who spent the same time in an environment with green light, and it turned out that blue light suppressed the synthesis of melatonin – the sleep hormone – up to twice as much as green. These are some of its effects.
Insomnia. If we normally begin to close our eyes at 11 p.m., being exposed to blue light can make it impossible for us to fall asleep until after 2 a.m., as demonstrated in an experiment by Steven Lockley.
Raise the temperature and improve memory. According to Gilles Vandewalle, researcher at the University of Montreal (Canada), blue light increases the heart rate and raises the temperature. And using electroencephalograms, he observed that when a person was exposed to this tonality of light while performing memorization tasks, the response in areas of the frontal and parietal cortex of their brain improved.
Good at “school” and in hospitals. According to the German chronobiologist Dieter Kunz, increasing the amount of blue in artificial light could increase performance and learning capacity both in schools and in offices and other indoor workplaces. Even improve the health of patients in hospitals. At the same time, “reducing exposure to blue light at night would protect shift workers from diseases such as cancer or cardiovascular problems, in addition to reducing insomnia problems in the entire population,” says Kunz.
Anti jet lag . Blue light could be used as therapy to set or reset the internal clock of people who, after a trip across multiple time zones or time zones, suffer from jet lag . The same could apply to students staying up late, astronauts in orbit on the ISS …
To drive. A recent study by the University of Bordeaux and the French CNRS has shown that to counteract the problems of drowsiness that appear when driving at night, it is enough to expose the person driving to monochromatic blue light. In this way, failures are reduced by half, practically the same as taking 400 mg of coffee, as revealed by the experiments.
Sensitive for the sunset. That we are so sensitive to blue light has to do with a photopigment called melanopsin that is especially sensitive to this wavelength (460-485 nm). This molecule is present in the photosensitive ganglion cells of the retina (pRGCs) of the human eye. According to Russell Foster, one possible explanation is that these cells are configured to detect the dominant wave light at twilight. “During sunset, the sun is close to the horizon and there is a relative enrichment of blue light in the dome of the sky because particles in the atmosphere make short light waves scatter more than the rest,” describes Foster.
