Lighting is a hallmark of our civilization. With artificial light we have turned night into day; extending working, shopping and entertainment hours, improving safety and security, and allowing us to transform the dark side of the planet into a twinkling map of human activity.
As is often the case, our technological development rapidly outpaces our evolutionary capacity, leaving our biology playing catch-up to the demands of modern life. Seemingly unwilling to ever take a step “backwards,” it is up to technology to overcome the issues it creates.
Just as renewable energy technology fights back against the environmental issues caused by industrialization; modern lighting technology is facing up to the problems associated with abundant artificial light – namely human health and wellbeing.
Research has shown that blue wavelengths, plentiful in white daylight, can excite a pigment called melanopsin that resides in the eye’s non-visual photoreceptors – technically referred to as intrinsically photosensitive retinal ganglion cells (ipRGCs). This sends stimulating signals to the body’s master clock that resides in the brain.
“The basics are, we know how your eye responds to light – that bit is proven,” explains Fenella Frost, marketing and business development director at PhotonStar Group. “We know there is a cycle, that you need more in the day and less at night. Within that, doing something is better than doing nothing. Fixed white light is terrible. Doing anything that’s more like nature has got to be good.”
The lighting industry is now experimenting with light to improve human wellbeing, and there is no better proving ground for this than healthcare. In the world’s biggest study on lighting applications to improve patient recovery, sunlight rhythms are being mimicked with artificial light inside a number of hospitals and plotted against healing from illness and injury.
At the Rigshospitalet Glostrup hospital in Copenhagen, 73 patients suffering from bleeding on the brain are monitored in rooms fitted with Chromaviso sun mimicking LED lighting system. Their hypothesis revolves around the idea that providing the patients with natural light patterns will synchronize their circadian rhythm, or body clock, with a schedule our evolutionary biology was used to until the last 150 years or so.
“The light itself is not healing, but it improves what you would expect as basic human functions,” said Torben Skov Hansen, Chromaviso’s head of innovation and quality assurance. “It’s like walking – entrainment to day and night is one of the basic functions we have. We need sleep each and every night, and we need it in constant occurrence. And it is light that is the main entraining factor. The main source to synchronization is the light and the daily pattern of light and darkness.”
The same technology was installed at the intensive care unit at Aarhus University Hospital in Aarhus, Denmark, where nurse Lone Moeslund and colleague Leanne Langhorn are now making clinical observations and gathering evidence that they hope leads to solid conclusions. The trauma unit deployment, which started in 2011 as a small implementation in a room with 3 beds, expanded in 2014 to cover 12 beds in total.
Research nurse Langhorn, a PhD specializing in rehabilitation medicine, brain traumas, and neurosurgery, is leading the trauma study at Aarhus. She grew interested in the circadian idea for practical reasons, among others. “The patients were a challenge for us,” she said. “They woke and they were not orientated and they were agitated, and I thought instead of giving them medicine it would be better to look at their surroundings, to see if we could do anything with the surroundings to calm the patients.”
Moeslund has already remarked on better recovery rates for suffers of brain trauma from car accidents, falls, strokes, aneurysms, and other conditions. “It’s really good for the patient. I believe that we’ve made a good circadian rhythm for them. It’s light that’s bright in the daytime and dark at nighttime. That must make a difference to them. I can’t conclude that for certain yet, but I think we are giving them a better circadian rhythm. And if they get a better sleep – we don’t know this yet, but we think they recover faster.”
Researchers at both Danish hospitals have also commented on the positive impact the light has had on staff too, with obvious knock on effects for patient recovery. If we all feel more awake in the day and sleep better at night, then we can all be healthier, calmer, more productive and therefore better at our jobs. Particularly useful for doctors and nurses but with huge implications for anyone exposed to artificial light.
This technology has not just come about because of scientific theory, but also because of the emergence of LEDs and the internet of things (IoT) in our increasingly smart buildings and cities. “The LED allows us to be a little bit more precise than incandescent because you can tune the spectrum,” noted Mariana Figueiro, acting director of Rensselaer’s Lighting Research Center.
It is also Lighting itself that “is undergoing a rapid transformation as LEDs become the number one source of light in buildings. This is the single most important driver for the growth of Bus-based lighting controls and their convergence with IT Networks,” which makes such systems possible – explains our last Lighting Controls report.
Whether it’s improving the productivity of office and factory workers, allowing our home to transition us into night and sleep, or improving the wellbeing of the sick and healthy, these changes to lighting technology can have a profound effect on society. They can calibrate the human body to achieve a desired objective.
As Bob Karlicek, the director of Rensselaer Polytechnic Institute’s Center for Lighting Enabled Systems and Applications, points out; “we don’t have the expression ‘mood lighting’ for nothing.”