Artificial Light: Safe for You, Safe for Earth
Innovators: Stephen Macknik & Susana Martinez-Conde
Innovations: Interconnected Light-Based Projects
From computers to televisions to movie theaters to cell phones, our modern culture has us surrounded by light-emitting screens and various sources of artificial light. We watch, we stare, we generally don’t even think twice about keeping our eyes continually fixed on these flickering light boxes or working for hours beneath subliminally flickering lighting.
Yet how much do we know about the effect these screens and lights have on us—on our eyes, on our brains? Fortunately, there are dedicated CHW research scientists devoting great time and energy to answering these questions—scientists who have already uncovered some extremely compelling and potentially life-changing answers.
How the brian processes light
In Stephen Macknik’s Laboratory of Behavioral Neurophysiology and Susana Martinez-Conde’s Laboratory of Visual Neuroscience at the Barrow Neurological Institute (BNI) of St. Joseph’s Hospital in Phoenix, Arizona, that intangible anti-matter known as “light” is the focus of not one but two highly innovative research projects and important patents.
With PhDs in neurobiology and post-doctorate positions with Nobel Prize-winning neuroscientist David Hubel, both Dr. Macknik and Dr. Martinez-Conde chose their careers in science as an ideal way “to contribute to progress.”
The brain “is the biggest mystery in science there is,” says Macknik. “As a doctor I can help an individual person, but as a scientist I may discover something that would help everybody.” And, working collaboratively, their two labs have effectively done just that.
The fuss about flickering
Macknik and Martinez-Conde currently hold patents for two interconnected light-based projects with far-reaching implications. First is an in-depth examination of the neural foundations of “flicker fusion,” the process by which flickering lights—on computer monitors, movies, television, and virtually all artificial lighting in the Western world—appear to be stable.
On your computer, for example, the flash rate is 60 hertz, an arbitrary number based on Thomas Edison’s early opinion of what caused flicker in light bulbs—and then turned into an industry standard with essentially no research behind it. But it has since been determined that certain flash rates can actually be dangerous for your brain and can even cause epilepsy in children: in a well-publicized 1997 case in Japan, an episode of the animated TV show Pokemon triggered seizures in viewers. More than 700 people, mainly school children, were rushed to hospitals after suffering convulsions, vomiting, irritated eyes and other epilepsy-type symptoms after watching the hugely popular cartoon.
Until now, it was not known why flicker is harmful or how to protect people from it and build our everyday devices so they don’t cause damage to the brain. But Macknik and Martinez-Conde have discovered that the interstimulus interval—the time between each flash—is what actually matters, not the flash rate. Their research has determined that it is even possible to make the flicker invisible if the interval between the stimuli is made very short. Alternately, by adding distance between each flash, you can make things look like they are flickering even if the flicker rate is unchanged.
The positive outcomes of this groundbreaking research are extensive. For starters, flickering lights and flicker devices such as computers and televisions can now be made more stable and efficient simply by putting the results of the research into practice in the manufacturing of these products. They can also be made safer for both epileptics and those who get excessive eye strain or headaches under normal artificially-lit working conditions, resulting in significant health benefits and increased productivity in the workplace.
Brightness and energy conservation
As complement to their flicker research, Macknik and Martinez-Conde have also recognized the significance of brightness in how the brain processes and sees light. Through their patented brightness project, they have learned that the brain integrates light over time, in a nonlinear fashion; as our brain processes a flickering light, it will get brighter for a certain amount of time but will then start to dim again. Thus, a short duration of light is actually perceived as brighter than a long duration. Consequently, if lights were made to flash five times less long, we would use five times less power—but the lights would still be brighter. Given that approximately 25% of all power consumption in the United States is used for lighting sources and devices, these findings are a momentous opportunity for major power conservation in our already energy-challenged nation. Indeed, we could achieve a power reduction in our lighting sources by as much as 600%!
Macknik and Martinez-Conde’s projects clearly demonstrate the need for a societal change in how we make our light bulbs and other lighting devices—even CFLs could be made much more efficient and much safer with the scientists’ patented research. It can also be applied to how light devices are made for the visually impaired, optimizing the devices to allow people to read better and for longer periods of time. Macknik and Martinez-Conde’s scientific approach is at once straightforward and groundbreaking: We must simply tune the temporal dynamics of our light sources to the temporal dynamics of the human brain—we need to make our lighting sources work the way we work.
The complex science of consciousness
Ultimately, it all boils down to an understanding of the basic science of consciousness. Macknik and Martinez-Conde attempt to solve some pretty daunting mysteries in their work, taking a step beyond the generally precise realm of science to the philosophical, even abstract field of human consciousness. How does consciousness work in the brain? How can inanimate neurons in the brain make us think? And how is it that part of our brain responds to something that we cannot consciously perceive? By studying flicker and brightness, they are actually able to determine which parts of the brain are conscious or not.
Since the moment Stephen Macknik and Susana Martinez-Conde arrived at BNI in 2004, and as their two laboratories have developed their innovative research projects over time, CHW has been an invaluable partner and resource for supporting the work of these two nationally recognized scientists, acquiring funding for their research and providing the expertise needed to carry their projects to patent. For Macknik and Martinez-Conde, the patents don’t represent an opportunity to just make money off of their work but as the one way to truly make the projects commercially viable and to make the contributions to progress that drew them to neuroscience from the start.
