Researchers at the Georgia Institute of Technology have developed a soft, wireless wearable device that can monitor sleep and processes related to brain health at home. The technology is intended to make it easier to conduct sleep research outside hospital settings and may contribute to a better understanding of the role of sleep in brain recovery and cognitive functions.
Good sleep is essential for brain function. During sleep, the so-called glymphatic system is active; this is a natural cleansing mechanism that removes waste products that accumulate in the brain during the day. This process plays a key role in memory formation, cognitive performance and the recovery of neural networks. When sleep quality declines, waste products can accumulate, which may affect memory and cognitive functions.
Wireless monitoring at home
Traditional methods for investigating brain activity and sleep, such as MRI scans and polysomnography, are costly, burdensome for patients and generally only available in a clinical setting. The research team led by W. Hong Yeo therefore developed a wearable alternative that can be used at home.
The new wearable uses near-infrared spectroscopy and wireless communication to continuously monitor physiological changes during sleep. Thanks to its soft and flexible design, the sensor can be worn comfortably, enabling researchers to study sleep in a natural home environment rather than a sleep laboratory. According to the researchers, this is the first soft, wireless and non-invasive wearable capable of continuously monitoring changes related to cerebrospinal fluid and the activity of the glymphatic system during sleep.
Insight into sleep processes
The wearable uses LEDs that emit light at specific wavelengths. This light penetrates the tissue and fluid near the brain, after which a photodetector captures the reflected light. The collected data is then transmitted wirelessly via Bluetooth to a paired device for further analysis.
The researchers emphasise that various factors can influence the measurements. These include breathing, changes in body posture, slight pressure differences on the forehead, movement and temperature fluctuations, all of which can affect the optical signals. For this reason, the system does not aim to measure the exact volume of cerebrospinal fluid, but rather to track changes and trends during sleep.
Although some of the measured signals may also originate from the skin, scalp or movement of the wearable itself, the researchers regard the technology as a promising tool for future sleep research. By making sleep monitoring more accessible and comfortable, they expect that the new wearable device can contribute to larger-scale research into sleep quality, the functioning of the glymphatic system and the relationship between sleep and brain health in everyday practice.
Wearable sleep trackers
Sleep trackers integrated into smartwatches, rings and mobile apps are becoming increasingly popular, but experts warn that they estimate rather than directly measure sleep. Most devices rely on heart rate and movement data to determine when users fall asleep, wake up and transition between sleep stages. While these algorithms accurately identify overall sleep patterns, they remain less precise than clinical sleep studies.
Researchers emphasize that wearables are most valuable for identifying long-term trends rather than interpreting data from a single night. They can help users recognize how lifestyle factors, such as alcohol consumption or late meals, affect sleep and encourage healthier habits. However, experts also warn against orthosomnia, an unhealthy obsession with achieving perfect sleep scores, which can increase stress and negatively affect sleep quality. Looking ahead, researchers believe wearables could play an important role in the early detection of conditions such as infections, depression and mental health relapse, supporting preventive and personalized care.
