Space travel changes the human brain, reveals new research.
Now scientists are trying to work out just what the long term effects are of changes in the brain during extended missions in space before NASA’s planned mission to Mars.
More people today are poised to explore space than ever before; and those who do will experience the effects of microgravity on the human body.
Neuroradiologist Dr. Donna Roberts conducted a study of the effects, published in the New England Journal of Medicine.
Roberts, of The Medical University of South Carolina, said: “Exposure to the space environment has permanent effects on humans that we simply do not understand.
“What astronauts experience in space must be mitigated to produce safer space travel for the public.”
NASA astronauts have experienced altered vision and increased pressure inside their heads during spaceflight aboard the International Space Station (ISS).
The conditions can be serious problems for astronauts.
To describe the symptoms, NASA coined the term visual impairment intracranial pressure syndrome, or VIIP Syndrome.
The cause of VIIP Syndrome is thought to be related to the redistribution of body fluid toward the head during long-term microgravity exposure, but the exact cause is unknown.
NASA has made determining the cause of VIIP Syndrome and how to resolve its effects a top priority.
Roberts proposed to NASA that MRI scans be used to investigate the anatomy of the brain following spaceflight.
She suspected subtle anatomical changes in the brains of astronauts during spaceflight might be contributing to the development of VIIP Syndrome.
She examined the brains and muscular responses of participants who stayed in bed for 90 days, during which time, they were required to keep their heads continuously tilted in a downward position to simulate the effects of microgravity.
Using MRI scans, Roberts evaluated brain neuroplasticity, studying the brain’s motor cortex before, during and after long-term bed rest.
Results confirmed neuroplasticity in the brain occurred during bed rest.
As Roberts evaluated the brain scans, she noted a “crowding” occurrence at the vertex, or top of the brain, with narrowing of the gyri and sulci, the bumps and depressions in the brain that give it its folded appearance.
The crowding was worse for participants who were on longer bed rest.
Roberts also saw evidence of brain shifting and a narrowing of the space between the top of the brain and the inner table of the skull.
She questioned if the same thing might be happening to the astronauts during spaceflight.
She also acquired brain MRI scans and related data from NASA’s Lifetime Surveillance of Astronaut Health program for two groups of astronauts: 18 who had been in space for short periods of time aboard the U.S. Space Shuttle and 16 who had been in space for longer periods of time, typically three months, aboard the ISS.
The researchers compared the brain images of the two groups of astronauts.
The results confirmed a narrowing of the brain’s central sulcus, a groove in the cortex near the top of the brain that separates the parietal and frontal lobes, in 94 percent of the astronauts who participated in long-duration flights and 18.8 percent of the astronauts on short-duration flights.
Cine clips also showed an upward shift of the brain and narrowing of the CSF spaces at the top of the brain among the long-duration flight astronauts but not in the short-duration flight astronauts.
Her findings concluded that “significant changes” in brain structure occur during long-duration space flight.
And, more importantly, the parts of the brain that are most affected — the frontal and parietal lobes — control movement of the body and higher executive function.
The longer an astronaut stayed in space, the worse the symptoms of VIIP syndrome would be.
To further understand the results of the study, Roberts plans to compare repeated post-flight imaging of the brains of astronauts to determine if the changes are permanent or if they will return to normal after some time back on Earth.
With NASA’s Mars expedition mission set to launch in 2033, there’s an urgency for researchers to collect more data about astronauts and understand the basics of human space physiology. A journey to Mars can take three to six months, at best.
During the two-year time period, crew members would remain on Mars, conducting exploration activities. The gravity on Mars is around one-third that of Earth.
Considering travel to and from Mars, along with the time on the surface, Roberts said the Martian expedition crew would be exposed to reduced gravity for at least three years.
To date, the longest continuous time in space was 438 days, a record held by Russian cosmonaut Valery Polyakov.
Roberts said: “We know these long-duration flights take a big toll on the astronauts and cosmonauts; however, we don’t know if the adverse effects on the body continue to progress or if they stabilize after some time in space.
“These are the questions that we are interested in addressing, especially what happens to the human brain and brain function?”
Study co-author Dr. Michael Antonucci added: “This study is exciting in many ways, particularly as it lies at the intersection of two fascinating frontiers of human exploration — space and the brain.
“We have known for years that microgravity affects the body in numerous ways.
“However, this study represents the most comprehensive assessment of the impact of prolonged space travel on the brain.
“The changes we have seen may explain unusual symptoms experienced by returning space station astronauts and help identify key issues in the planning of longer-duration space exploration, including missions to Mars.”
Space travel permanently changes the brain – New York Post