Mariana Figueiro, director of the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute, continues to enhance the lighting treatment developed for older adults with Alzheimer’s disease. The research team recently announced a US$ 3 million grant renewal from the National Institute on Aging (NIA).

Figueiro has demonstrated that providing light exposure of certain amounts and qualities throughout the day can improves sleep patterns, sociability, and agitation, while decreasing symptoms of depression. With the latest grant renewal, Figueiro and her team will fine-tune their approach to dosage of light, working in long-term health care facilities to find the optimum brightness and duration that makes a quantifiable difference in a patient’s day-to-day life.

(image: Osram)

“What we have proven is that light therapy is a non-pharmacological intervention that makes a significant difference in the overall health of older adults living with Alzheimer’s and dementia,” she said. “People we talk to are hoping to be able to reduce the number of pills these individuals must take every day. And we tend to forget how hard this disease is on caregivers. In addition to helping the patient, finding ways to help caregivers is very important.”

Figueiro’s work has shown that exposure to bright, blue-hued light throughout the day signals to the body’s internal clock that it is daytime, promoting wakefulness. Then as evening approaches, dim, warmer orange-hued light tells the body that it’s time to rest. The flat, constant light found in most nursing homes just isn’t strong enough to properly regulate the body’s circadian rhythms.

The researcher pointed out that Alzheimer’s patients usually stay in nursing homes with weak lighting, so the research team is working on increasing light intensity as well as tuning it to a more bluish color. Figueiro envisions a future in which all rooms in assisted-living facilities and nursing homes have bright lights automatically providing patients with the light therapy she is perfecting. However, the researcher also noted that people with different health conditions require customized lighting therapy as well. Light is a key factor in establishing and maintaining the body’s circadian rhythms, which are critical to overall health, addressed Figueiro.

“The science is solid,” she said. “The work with the Alzheimer’s patients is where we’re learning everything about how we can implement these solutions, but I think the future is to expand the range of applications by utilizing our research in a wide spectrum of populations.”

Her team at the LRC is already investigating other uses. For example, they are testing personal sensors and apps that can be used to prescribe optimum lighting schemes to maintain an internal routine. Beyond that, she sees the science behind light therapy applied to the general population as a kind of “light fitness.”