The Lighting Research Center (LRC) at Rensselaer Polytechnic Institute has earned the notable distinction of receiving one of only 13 first-ever research grants awarded by the U.S. Green Building Council (USGBC). The $250,000 grant will fund research for a project titled “Quantifying the Impact of Daylight and Electric Lighting on Student Alertness, Performance, and Well-being in K-12 Schools.”
The project team intends to scientifically quantify the impact of daylight design on students’ well-being and performance in K-12 schools and investigate the underlying biological mechanisms associated with this possible link. The project team includes principal investigator Assistant Professor Mariana Figueiro, Ph.D., and co-investigators Professor and LRC Associate Director Russ Leslie, AIA, FIES, LC, and Professor and LRC Director Mark Rea, Ph.D.
“We hypothesize that if light has an impact on students’ performance and well-being, it is by promoting their circadian entrainment to the solar day, especially in winter months,” says Figueiro. “Those who are not exposed to enough daylight will experience a more pronounced delayed circadian phase, which will result in sleep problems and more severe stress.”
In response to the earth’s 24-hour cycle, all species have evolved circadian rhythms (e.g., sleep/wake behavior) that repeat approximately every 24 hours. In humans, circadian rhythms are synchronized, or entrained, to the solar day most strongly by the Earth’s natural light/dark cycle. Lack of synchrony between light and dark and sleep/wake cycles may lead to sleep deprivation, as well as symptoms of stress, mood disorders, and perhaps immune system deficiencies. In adolescents, sleep deprivation has been linked to their inability to fall asleep at appropriate evening hours and their need to get up early for school the following morning.
Figueiro, Leslie, and Rea will test the hypothesis that a lack of entrainment to the 24-hour solar day, due to reduced daylight availability in winter months, is the underlying mechanism linking daylight to well-being and performance.
“If the lighted environment in schools promotes circadian entrainment, it will help students fall asleep earlier, and therefore reduce their sleep deprivation. In turn, students should feel better and perform better in school,” Figueiro says.
In this project, the research team will select schools that have “good” and “bad” daylighting designs, evaluated using existing screening tools. They will ask students to participate and complete a number of different measures of psychosocial stress and sleep quality. Students will also be administered standardized performance tests.
The project team says that in order to link the impact of daylight and electric lighting on students’ performance and well-being, it is necessary to quantify the actual amount of daylight or electric light that students are being exposed to — specifically, the kind of light that stimulates the circadian system. Students’ daily light exposures will be measured using a personal circadian light meter, called the Daysimeter, which was invented at the LRC and has been used in previous circadian light studies.
The final outcome of the project will be a set of guidelines for architects, designers, and school administrators to enable the development of school building designs that maximize students’ health, well-being, and performance.
The project unites the LRC’s ongoing research efforts in two fields: daylighting, and light and human health.
The project team will be aided by Professor Mary Carskadon, Ph.D., E.P. Bradley Hospital Chronobiology and Sleep Research Laboratory (associated with Brown University), who will provide guidance and consultation on the experimental design and assist in reviewing and interpreting study data.