Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Develop Light-Treatment Device to Improve Sleep Quality in the Elderly

02.06.2009
Sleep disturbances increase as we age. Some studies report more than half of seniors 65 years of age or older suffer from chronic sleep disturbances.

Researchers have long believed that the sleep disturbances common among the elderly often result from a disruption of the body’s circadian rhythms—biological cycles that repeat approximately every 24 hours.

In recent years, scientists at Rensselaer Polytechnic Institute’s Lighting Research Center and elsewhere have demonstrated that blue light is the most effective at stimulating the circadian system when combined with the appropriate light intensity, spatial distribution, timing, and duration. A team at the Lighting Research Center (LRC) has tested a goggle-like device designed to deliver blue light directly to the eyes to improve sleep quality in older adults.

“Light and dark patterns are the major synchronizer of circadian rhythms to the 24-hour solar day,” said Mariana Figueiro, Ph.D., Lighting Research Center Light and Health Program director and principal investigator on the project. “Light stimulus travels through the retina, the light-sensitive nerve tissue lining the back wall of the eye, to reach the master clock in the brain. However, a combination of age-related changes in the eye and a more sedentary lifestyle may reduce the amount of light stimulus reaching an older person’s retina, therefore reducing the amount of light for the circadian system.”

As we age, the lens in the eye thickens and the pupil shrinks, reducing the amount of light passing through to the retina. Making matters worse, in some cases, such as with persons with Alzheimer’s disease, the circadian system may require a stronger light stimulus due to deteriorating neural processes in the brain. These physical and neural changes can lead to muted signals to the circadian system. Factor in environmental influences, such as an indoor lifestyle with less access to daylight, and you have a perfect scenario for the development of irregular sleep-activity patterns, according to Figueiro.

The research team explains that a marked increase in daytime lighting levels can counteract the age-dependent losses in retinal light exposure by providing a stronger signal to the circadian system. However, the color and intensity of commercially available lighting systems, like those used in senior residences, assisted-living facilities, and nursing homes, are designed for visual effectiveness and minimal energy use and not necessarily efficacious for generating light to stimulate the older circadian system.

Commercially-available “white” light sources advertised to treat circadian-related sleep disorders are usually very bright light and can cause glare and compromise compliance.

In this project, the light-treatment prototype tested by Figueiro’s team was developed by Topbulb.com, LLC, based on prior LRC light and health research. The device offers an alternative approach using specially designed goggles that deliver blue light spectrally tuned for optimum circadian response.

“The goal of this phase of the development project was to create a device in a smaller form factor or envelope that allowed for social inclusion and end-user mobility, while still delivering the required dose of light,” said Topbulb.com Senior Developer Philip H. Bonello, Ph.D.

The device was worn by eleven subjects between the ages of 51 and 80 years of age. Each subject was exposed to two levels of blue light (about 50 lux and 10 lux) from the personal light-treatment device for 90 minutes on two separate nights. Blood and saliva samples were collected at prescribed times to assess levels of nocturnal melatonin, a hormone used as a marker for the circadian clock, with high levels at night when a person is in a dark environment and low levels during the day.

After only one hour of light exposure, the light-induced nocturnal melatonin suppression level was about 35 percent for the low light level and about 60 percent for the high light level. In addition, the higher level of blue light suppressed nocturnal melatonin more quickly, to a greater extent over the course of the 90-minute exposure period, and was maintained after 60 minutes.

Having demonstrated its stimulation effect on the circadian system, the researchers believe the device could be subsequently used to increase sleep consolidation and efficiency in older subjects when worn for a prescribed duration at an appropriate time.

“The study suggests that the light goggles might be a practical, comfortable, and effective way to deliver light treatment to those suffering from circadian sleep disorders. The next steps are to conduct field studies where we will be testing the effectiveness of this personal light-treatment device on those suffering from circadian-related sleep disorders, while also verifying the acceptance of the a device among the test groups,” said Figueiro.

Figueiro carried out her research with LRC scientists Andrew Bierman, John Bullough, Ph.D., and Mark Rea, Ph.D. They co-authored a paper detailing the study, “A Personal Light-Treatment Device for Improving Sleep Quality in the Elderly: Dynamics of Nocturnal Melatonin Suppression at Two Exposure Levels,” which was recently published in Chronobiology International, Volume 26 Issue 4, 726.

This study was supported by the National Institute on Aging (1R41AG029693) through a Small Business Technology Transfer grant to Topbulb.com, LLC, a commercial and residential resource for light bulbs.

About the Lighting Research Center
The Lighting Research Center (LRC) is part of Rensselaer Polytechnic Institute of Troy, N.Y., and is the leading university-based research center devoted to lighting. The LRC offers the world's premier graduate education in lighting, including one- and two-year master's programs and a Ph.D. program. Since 1988 the LRC has built an international reputation as a reliable source for objective information about lighting technologies, applications, and products. The LRC also provides training programs for government agencies, utilities, contractors, lighting designers, and other lighting professionals.

Mary Cimo | Newswise Science News
Further information:
http://www.lrc.rpi.edu
http://www.rpi.edu

More articles from Health and Medicine:

nachricht NTU scientists build new ultrasound device using 3-D printing technology
07.12.2016 | Nanyang Technological University

nachricht How to turn white fat brown
07.12.2016 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>