The Lighting Research Center (LRC) has designed a pair of goggles that deliver blue light directly into the eyes. This new device is said to improve the quality of sleep for older adults. Many elderly suffer from serious sleep disturbances often times as a result of changes to their circadian rhythm. In brief, the circadian rhythm refers to the body’s 24 hour sleep/wake cycle, which relates to one’s exposure to light and shifts in hormone levels.
Many recent studies over the past few years have demonstrated the effectiveness of blue light in stimulating the circadian system. All types of light travel through the retina to the circadian clock in the brain. Unfortunately, several changes to the eyes and brain as well as lifestyle adjustments come with age, which can seriously impact the amount of light stimulus reaching the retina, therefore affecting the circadian clock. In addition, our lenses thicken and our pupils shrink with age, hence further reducing the amount of light that can pass through the retina.
Furthermore, the elderly may suffer from mental health conditions, such as Alzheimer’s disease, that require even more light to keep the circadian rhythm in tact because of weaker neural connections in the brain. Less time spent outdoors also reduces the amount of daylight taken in preventing a good night’s sleep.
“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."
The light-induced nocturnal melatonin was suppressed by about 35% with low levels of light exposure and about 60 percent with high levels of light after only one hour of wearing the glasses. Nocturnal melatonin appeared to be more rapidly suppressed and sustained with higher levels of blue light.
The study provides hope that a practical, comfortable, and effective solution may soon be available for those suffering from circadian sleep disorders.
Light-treatment Device To Improve Sleep Quality In The Elderly