The dark days of winter offer a powerful reminder of just how important light is to our health and well-being. Recently published research on light and lighting confirms that, perhaps more than any other element in a space, light has a profound effect on how design impacts occupants.
Efforts to conserve energy have led to the promotion of alternative sources of light to replace inefficient incandescent bulbs. The most common substitutes are halogen and compact fluorescent lamps (CFLs). However, occupants often dislike the quality of light produced by these bulbs.
As reported in the journal Ergonomics, researchers at the Institute for Experimental Psychology in Dusseldorf, Germany, decided to test whether subjects in fact experienced the light from these two sources differently. Subjects were asked to perform two tests — a color discrimination test and a proofreading test — under CFL or halogen lighting of comparable color temperature at either low (70 lx) or high (800 lx) illuminance.
They found that illuminance positively affected proofreading but that CFL lighting negatively affected color discrimination performance. There were no differences between light sources in terms of self-reported physical discomfort and mood state, but the majority of the participants correctly judged halogen lighting to be more appropriate for discriminating colors.
“The findings hint at the color-rendering deficiencies associated with energy-efficient CFLs,” the researchers concluded.
In another color-related study, researchers at Ohio State University found that light color can significantly affect one’s mood. By exposing hamsters to different colored night lights, they discovered that red is the least disruptive color to use for a night light.
The red night light resulted in significantly less evidence of depression-like symptoms and changes in the brain linked to depression, compared with those that experienced blue or white light. Blue light produced the worst effects on mood-related measures, followed closely by white light. According to the study, only those hamsters that had total darkness at night fared better than those exposed to the red light.
Although the results are inconclusive for humans, the researchers believe the findings may have important implications for humans. For example, people who work night shifts, such as healthcare workers and caregivers, are particularly susceptible to mood disorders. Moreover, others may benefit from limiting their exposure to light from computers, televisions and other electronic devices at night.
“If you need a night light in the bathroom or bedroom, it may be better to have one that gives off red light rather than white light,” the researchers advise.
It makes sense that light affects those who can see, but what about those who are visually impaired? After all, light is a visual stimulus, but does it also stimulate other areas of the brain?
A recent study with people who are completely blind confirms that our sensory systems are incredibly complex. Researchers at the University of Montreal and Brigham and Women’s Hospital in Boston determined that light enhances brain activity during a cognitive task even in people who are totally blind.
“Light doesn’t just allow us to see, it tells the brain whether it’s night or day, which in turn ensures that our physiology, metabolism and behavior are synchronized with environmental time,” explained senior co-author Julie Carrier. “For diurnal species like ours, light stimulates day-like brain activity, improving alertness and mood, and enhancing performance on many cognitive tasks.”
The results indicate that the subjects’ brains can still “see,” to detect, light via a novel photoreceptor in the ganglion cell layer of the retina, different from the rods and cones we use for sight.
The study also confirmed previous research that suggests blue light might enhance alertness. During a cognitive test, less than a minute of blue light activated regions important to perform the task; these regions are involved in alertness.
“These findings support previous studies done with sighted individuals, which linked seeing slightly blue-ish light to being more alert,” environmental psychologist Sally Augustin said.
All designers work with color and light. These studies provide further insight into how these two basic elements can be used to enhance brain function and mood, thus improving occupants’ quality of life, whether they are patients in a hospital or homeowners who just want to get a good night’s sleep.
Michael J. Berens is a freelance researcher and writer with more than 30 years of experience in association communication and management.
This article was provide by Multibriefs.
