We know that spacetime affects our bodies, from our brains to our bones, but scientists don’t really know the details. In a new study, researchers looked at how the length of space travel and the time between them can affect the water in a person’s brain.
This cerebrospinal fluid, stored in the brain in four sacs called ventricles, helps to protect the brain. It is also involved in cleaning cellular waste and delivering nutrients from the blood.
Researchers from the University of Florida, NASA Johnson Space Center and other institutions in the US have found a way in which space flight increases the size of the ventricle and the amount of fluid in the brain depends on other factors, including the length of time that astronauts spend in space, and the average time. their space travel.
“These findings show that the size of the ventricles increases with air travel and the duration of the task,” wrote neuroscientists at the University of Florida Heather McGregor and colleagues in their published paper.
In addition, “rest periods of less than three years may not allow enough time for the ventricles to regain their compensatory capacity.”
An increase in the size of the ventricle and some of the fluid in the brain is something that has also been observed in previous studies, and it is accompanied by the movement of the brain inside the skull in microgravity, which helps to redistribute the fluid.
Using MRI scans of 30 astronauts, the researchers built on these previous studies to find that the longer the space, the increased the size of the ventricle – up to six months or more, where the change is seen as the surface.
It is thought that the swelling of the ventricles of the brain represents a recovery mechanism during flight, which allows the brain to adapt to changes in the fluid in the cerebrospinal fluid. When they return to Earth, the cerebrospinal fluid slowly returns to normal.
“Although it seems counterintuitive that there would be significant changes in short-term subjects, this may indicate an early, reversible change that gradually reverses over time,” the researchers explain.
For the seven astronauts who had a break of less than three years between missions, the growth of the ventricle was not so obvious. The team suggests that this means that there is not enough time for the ventricles of the brain to contract and reset, to deal with the increased amount of brain fluid.
The videos also showed that the more previous missions an astronaut has done, the more the ventricles become enlarged after a mission. It’s as if the astronauts’ brains were “unadapted” due to early development, or they developed a better ability to cope with the challenges of spaceflight, the researchers say.
“This finding suggests that the brain is affected by the frequency of multiple flight events and possibly by changes in microgravity and the flight environment,” the researchers wrote.
One of the problems for scientists is that there are not many people who go to space regularly – 636 people in total at the time of writing. Analyzing the effects of spaceflight on large groups of people should be important in order to learn more about how the bodies and brains are affected.
The study did not go to the health consequences of changes in the size of the ventricle and levels of fluid in the brain, but it is clear that changes in the brain occur, and are affected by the length of the mission and the frequency. In the past, this extra cerebrospinal fluid has been linked to vision problems in astronauts.
With long-distance missions planned to the Moon and Mars in the coming years, we need to understand as much as possible about what astronauts will do for themselves – and nowhere is that more important than in the brain.
“These findings reveal the regions of the human brain that change with spaceflight,” the researchers write.
Research has been published in Scientific Reports.