Astronauts going on their first long-term space mission have found differences in their brains compared to the brains of more experienced astronauts and those of people who’ve never been to space — particularly growth in the spaces in the brain where cerebrospinal fluid flows, a new study finds. study finds.
Although scientists knew that changed in space and possibly damages the brainThe study is one of the first to address a specific aspect of brain health in space using a comparative method and a relatively large group of astronauts.
Cerebrospinal fluid, the clear fluid that surrounds the brain and spinal cord, behaves differently in microgravity, leading the researchers to wonder what impact spaceflight might have on these areas. The findings could help scientists better understand how being in space affects the human brain.
Related: Long space missions could alter astronauts’ brain structure and function
These studies are especially important for long-term missions; NASA plans to send astronauts to the moon in the coming years as part of the agency’s mission Artemis program and, eventually, to Mars – a journey estimated to take nearly two years†
“These findings have important implications as we continue to explore space,” said senior author Dr. Juan Piantino, an assistant professor of pediatrics at Oregon Health & Science University School of Medicine’s Division of Neurology, in a statement†
The researchers used magnetic resonance imaging (MRI) to scan the brains of 15 astronauts, nine of whom were “beginners,” meaning they were completing their first mission in space and had no previous space flight experience. Sixteen ground-based NASA employees Johnson Space Center in Houston served as a control group for comparison purposes.
Researchers examined the perivascular spaces (PVS), the spaces where cerebrospinal fluid flows in the brain, of each astronaut before and immediately after their time in space. They also took scans one, three and six months after the astronauts returned to Soil†
The researchers found that the total PVS volume of novice astronauts increased after their journeys to space. In contrast, the PVS of experienced astronauts did not show this growth – in fact, their total PVS volume actually decreased. This may indicate that their brains “reached a kind of homeostasis,” Piantino said in a statement. In other words, their brains may have been more adapted to microgravity after previous spaceflights.
In fact, the researchers found that the total PVS volume of experienced astronauts before their current flight tended to be higher, and that this base volume correlated with the previous amount of time spent in space. While none of these trends were statistically significant, meaning they could have happened by chance, they fit with previous research suggesting that changes in astronauts’ brains depend on total time spent in space and the frequency of space missions. .
Although PVS volume gradually increases as people age, members of the Earth-based control group did not experience the kind of PVS changes that the novice astronauts showed. The PVS are part of the glymphatic system, which removes waste products from the brain, usually during sleep. Other health problems — such as dementia and hydrocephalus, or the buildup of too much fluid in the brain’s ventricles — can affect these spaces. The results of the new study may help address the effects on these brain structures that stem from health problems on Earth.
“These findings help to understand not only fundamental changes that take place during spaceflight, but also for people on Earth who suffer from diseases that affect the circulation of cerebrospinal fluid,” Piantino said in the statement.
The results, as well as the findings of other studies examining the effects of spaceflight on the brain and cerebrospinal fluid, indicate the profound influence of gravity about the evolution of man and all life on earth. The body and brain did not evolve to be in a microgravity environment, and previous research has already provided clues about the variety of health effects associated with time spent in microgravity, such as brittle bones and problems with balance†
This research “forces you to think about some basic fundamental questions of science and how life evolved here on Earth,” Piantino said.
The study was published May 5 in the journal Scientific Reports†
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