In one of the laboratories in Germany, volunteers are paid for helping to investigate one of the most serious problems of space travel: how to provide cosmonauts the best sleep at night? The underground scientific research laboratory is surrounded by a forest near the German Cologne. The walls are white, softly lit, there are no windows and only a few pictures. In the room there is one bed, a computer and an alarming picture with an unearthly landscape, with a giant flower plant and a strange futuristic cosmic land. On the ceiling fixed cameras that track each step.
Once in a laboratory isolated from the whole world, you can completely lose the routine of the day and night. Everything becomes detached from reality, as if it does not happen on Earth. Actually, the creators of the laboratory belonging to the German Space Agency sought this. Envihab – an ideal environment for scientists and doctors, where they can test the impact of space flight on the human body.
In one of the latest experiments, the influence of lack of sleep – a real problem for astronauts at the International Space Station (ISS) – is being studied. "In principle, they could sleep enough, about eight hours a day," says Eva-Maria Elmenhorst, who conducts the study. "But most astronauts sleep for five to six hours, and that's not enough."
Many of us want to sleep all day, and only strong coffee allows us to keep on our feet. It's one thing to get up at 4:15 in the morning to fly to Germany and talk to Elmenshorst, and another to be an astronaut flying around the planet at a speed of 27,000 km / h a few centimeters from the cold vacuum of the cosmos. Any wrong decision, oversight or loss of concentration can mean a choice between the life and death of the astronaut and the rest of the crew. What is it like to just dock a space ship weighing several tons, sleeping only five hours?
However, it's not so easy to sleep well in space. There are no beds or pillows – a sleeping astronaut is tied to the wall in a sleeping bag. And that is not all. "Probably, there are several reasons why they do not sleep properly," says Elmenhorst. "Isolation, sunrise every 90 minutes and the noise of the ventilation system – all this interferes. Often astronauts are forced to work in shifts, observing experiments or seizing supply ships. "
To investigate how this lack of sleep affects the work of astronauts, the Elmenhorst team subjected groups of paid volunteers to experiments with sleep deprivation. "We want to show how the lack of sleep affects cognitive functions, and why some people cope better than others."
Like astronauts, she hopes that the research will benefit the shift workers on Earth and others – doctors and nurses – who work long hours, making decisions about life and death, struggling with lack of sleep. In Germany alone, according to Elmenhorst, about 16% of employees regularly work on shifts, and many workers, often working in critical places, sleep less than the recommended eight hours per day.
Volunteers in Elmenhorst's experiments were given a number of daily tasks, including exercises with memory, reaction tests and repetitive computer games. For five nights they were allowed to sleep for only five hours. This was followed by a recovery period with eight hours of sleep, followed by a crazy marathon at thirty-eight hours without sleep.
Doctors controlled the activity of the brain of their subjects using a variety of electrodes, took blood samples and conducted an MRI scan.
"We are interested in the fundamental mechanisms of the brain that control sleep," says Elmenhorst. "Even one night without sleep leads to hormonal changes in the body."
Volunteers who were motivated primarily by money, sitting, looking at the TV and chatting for two weeks, proved to be more difficult than they imagined. "It was difficult to stay awake," says Lucas, a student who took part in the study. "Someone always kept us awake."
"The only thing we could do was talk to each other, watch TV or play with the laptop," says another Magdalena volunteer who is preparing to become a teacher. "There was always someone who said: Magdalena, are you asleep? Wake up, Magdalena! "
To ensure that volunteers are not slumbering, they were constantly monitored by members of the research team – who sat with them or watched them on the monitors of the laboratory. If the eyes of the volunteer were closed too long, the scientists woke him up.
There were days, and Lucas realized that his memory and agility were deteriorating. "I noticed that we were worse off taking tests," he says. "Now I try to sleep as much as possible – no more night-time get-togethers."
In addition to identifying the expected decline in mental performance, the research team found even more disturbing biological changes in volunteers. "We showed that five hours of sleep at night for five days slows down the metabolism of glucose, and hormonal changes occur in the body," says Elmenhorst. This correlates with studies suggesting that people who regularly work in shifts suffer disproportionately from diabetes and high blood pressure.
The ultimate goal of the current study is to develop the best daily schedules for astronauts so that they do not get too tired. As long missions become more common and mankind moves toward cosmic civilization, providing enough sleep for astronauts becomes very important.