A new algorithm could help people learn how to avoid tossing and turning at night, and improve their overall sleep quality.
Researchers from Lancaster University in the U.K. and Northwest University in China have created new smart watch algorithms that identify some of the underlying causes of poor sleep quality.
The new software—dubbed SleepGuard—estimates sleep quality by tracking a combination of different non-biomedical factors like body movements, sounds related to sleep disorders and ambient lighting. SleepGuard also provides the wearer with practical advice to help them improve their sleep quality.
“Our project aims to unlock the full potential of off-the-shelf consumer smartwatches, taking advantage of their sophisticated suite of sensors to gain a fuller understanding of a wearer’s sleep patterns,” Petteri Nurmi, PhD, Lecturer from Lancaster University and co-author of the work, said in a statement.
The algorithm works in tandem with a smartwatch that includes sensors that can identify body and hand movements during sleep, such as an accelerometer, gyroscope and orientation sensors. The microphone in the smartwatch also captures the ambient noise in the room, as well as whether the user is snoring or talking during sleep. A light sensor also captures any illumination that may be occurring in the sleep environment.
Rather than reading biomedical signals, SleepGuard focuses on capturing physical activities that occur during sleep. The researchers found that sleep quality is linked to characteristics in body movements and health-related factors could be discovered through sounds and the sleeping environment itself.
After testing the technology on 15 volunteers, the researchers found that SleepGuard could estimate the sleep-quality with a similar accuracy of consumer-grade sleep monitors. The product is also able to obtain crucial information about the factors behind sleep quality, helping users identify the root causes.
SleepGuard can capture the four basic sleep postures—sleeping on a person’s back, front and each side—because arm position is strongly linked to posture. It also recognizes the three common hand positions that aid in identifying sleeping problems.
For example, placing a hand on the abdomen can indicate discomfort, placing a hand on the chest can cause nightmares due to pressure on the heart, and placing a hand on the head can put excess pressure on shoulder nerves and cause arm pain due to restricted blood flow.
SleepGuard also counts the number of times the user rolls over during sleep.
“When compared to existing sleep monitors on the market, SleepGuard is able to report a wider range of sleep events and provide wearers with a better understanding for the causes of their sleep problems,” Liqiong Chang, PhD, assistant professor at Northwest University and co-author of the research, said in a statement.
While medical grade technology is more accurate than SleepGuard, the technology is advantageous because it could be inexpensive and easy to use at home.
The researchers hope SleepGuard will help users have a deeper and more comprehensive understanding of what happens when they sleep, enabling them to make informed decisions to improve their sleep quality, and ultimately their health. Some ways to improve sleep quality involve altering the lighting in the bedroom, addressing possible noise, and changing postures and hand positions.
“Sleep quality has been shown to depend on a wide range of factors, such as ambient light, noisiness as well as breathing patterns, sleeping postures and bedtime routines,” Zheng Wang, PhD, Senior Lecturer at Lancaster University and co-author of the research, said in a statement. “Without details of the sleeping environment and the individual’s postures and movements across sleeping stages, the root cause of poor sleep cannot be captured and therefore addressed.”
The study was published in ACM Digital Library.