Space Travel Could be Making Astronauts' Brains More Fragile

Wednesday, 01 November 2017 - 8:40PM
Wednesday, 01 November 2017 - 8:40PM
Space Travel Could be Making Astronauts' Brains More Fragile
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As a species, we probably need to face facts: the human body really isn't designed for zero-gravity environments. Years of evolution have tailored us perfectly to every aspect of Earth's environment, which means that the moment we're removed from our natural habitat and leave the planet, the body starts showing strange side effects thanks to the lack of gravity.

A new study, published by the New England Journal of Medicine, details the differences that have been spotted in MRI images of astronauts' brains from before and after they spend time in space. Most interestingly, apparently the astronauts' heads show less fluid between the brain and the skull, leading to a series of mild but not entirely insignificant side effects upon returning to Earth.

For one thing, less fluid cushioning the brain means that the astronauts are more susceptible to head injuries - while it's not advisable to take a blow to the head under any circumstances, this may well affect astronauts in worse ways because their brains have less fluid to slosh around in when jolted.

Scientists also theorize that this might have something to do with the reports from some astronauts that they experiences changes in their vision while in space or after returning home - although it is important to note that not all astronauts experience eyesight issues.

According to Donna Roberts of the Medical University of Carolina, who was lead author on the new study, this may be the result of astronauts' brains floating within their skulls thanks to the zero-gravity environment:

Opening quote
"One of our theories is that because there is no longer the force of gravity pulling the brain down, the brain moves upward."
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With the brain potentially shifting within astronauts' skulls, the fluid that protects the brain may drain down to fill an area below the brain that's not normally protected, reducing the amount of fluid that is present around the rest of the brain.

This could also explain those differences in vision that the astronauts experience, as it may be possible that as the brain floats up, it pulls on the optic nerves, straining vision and potentially changing the way the signals from the eyes are communicated.

The initial study that's been undertaken is far from a complete look at the effects of space travel on the brain, and there's a lot of conjecture and theorizing going on as to what causes changes in astronauts' brains. Further studies - particularly tests with larger pools of volunteers to provide more data - are crucial to learning exactly what's going on.

That said, this is far from the only health risk that's caused by prolonged time in zero gravity. Astronauts have to constantly exercise in order to avoid their muscles withering away from disuse while in space, but that certainly hasn't stopped anyone from wanting to blast off into orbit.

Astronauts' brains are hardly at a terrible risk due to their time in space - but considering how cool space travel is, it's unlikely that a threat of permanent deterioration would keep people from wanting to explore the cosmos anyway.
Science News