If you thought you had trouble sleeping in your own bed, try sleeping in microgravity, strapped into a sleeping bag in Earth’s orbit at over 17,000 miles per hour. Astronauts on the ISS find it difficult to maintain a normal sleep pattern in the artificial day-night cycle, which leads to poor sleep habits.
To monitor astronauts’ sleep patterns, a group of scientists from Aarhus University in Denmark developed a small device to track astronauts’ sleep in space. The device is called ear-EEG (ear-ElectroEncephaloGraphy), and it can be worn on the ear like headphones. Once in place, the ear-EEG will monitor the electrical activity of the astronauts’ brains while they sleep. According to Aarhus University, the device works by detecting very small changes in the surface tension of the skin inside the ear, which are caused by electrical activity originating from neurons in the brain.
“In the future, we’ll probably be in space a lot more often, and have to stay there for longer. And it’s important to understand how it affects our sleep,” Eskild Holm Nielsen, dean of the Aarhus University Faculty of Technical Sciences, said in a statement. “Being able to make a precise physiological characterization of the sleep will also help us find out how we can help astronauts get a better night’s sleep in space.”
Astronauts are often housed in small rooms about the size of a telephone booth, where they sleep in a sleeping bag strapped to the wall. They also operate on a day-night schedule, which is enforced by changing the lighting settings on the space station from light to dark to allow them about 6-8 hours of sleep each day. In addition, they lack everyday comforts such as resting on a pillow because there is no gravity to lift the head up, and the feeling of a blanket covering them.
Ear-EEG will be used by astronauts aboard the International Space Station as well as here on Earth to measure the difference in their sleep patterns between Earth and space. The data will help scientists understand how spaceflight affects astronauts’ sleep at a physiological level, which can affect their cognitive functions, such as decision-making skills, memory, judgment and concentration. Scientists are also interested in measuring how different environments affect a person’s sleep pattern.