Space Travel Continuously Changes Astronaut Brains During Flight, Says New Study

Astronauts do have different brains than an ordinary human being, and it turns out it's one of the effects of prolonged time of spaceflight. A recent study by the University of Michigan revealed that the human brain tends to compress and expand during spaceflight.

According to the report from the university website, the team of researchers observed MRIs before and after space missions to determine the extent of transformation that occurs in the astronauts' brains. Participants included 12 astronauts who spent two weeks as shuttle crew members and 14 who spent six months on the International Space Station.

In the study, published in Nature Microgravity, every single one of the subjects had increases and decreases in gray matter in different areas of the brain. The scientists also found that the longer time spent in space, the more pronounced the changes tend to be.

"We found large regions of gray matter volume decreases, which could be related to redistribution of cerebrospinal fluid in space," lead researcher Rachael Seidler said. "Gravity is not available to pull fluids down in the body, resulting in so-called puffy face in space. This may result in a shift of brain position or compression."

Additionally, there is an increase in gray matter in parts of the brain that control movement and process sensory information from the legs. This is likely due to the altered way astronauts use their limbs in microgravity. It proves the plasticity of the brain, but these changes are equivalent to a person learning and practicing a new skill for 24 hours every day.

"In space, it's an extreme example of neuroplasticity in the brain because you're in a microgravity environment 24 hours a day," Seidler pointed out.

The changes in brain changes could mean new connections between neurons. To discover more about the effects of spaceflight, Seidler is leading a separate long-term study that will focus on how long the brain changes last and its repercussions on cognition and physical performance.