Astronauts heading to Mars could risk chronic dementia
Will astronauts heading to Mars be putting their own brain health at risk? A new study out of the University of California, Irvine found that exposure to highly energetic charged particles similar to those that hit astronauts on long space trips led to brain damage in test rodents. The damage included dementia and other cognitive impairments.
The study was published in Nature’s journal Scientific Reports.
“This is not positive news for astronauts deployed on a two-to-three-year round trip to Mars,” Charles Limoli, a professor of radiation oncology in UCI’s School of Medicine, said in a press release. “The space environment poses unique hazards to astronauts. Exposure to these particles can lead to a range of potential central nervous system complications that can occur during and persist long after actual space travel – such as various performance decrements, memory deficits, anxiety, depression and impaired decision-making. Many of these adverse consequences to cognition may continue and progress throughout life.”
The research team initially exposed rodent subjects to charged particle irradiation at NASA’s Space Radiation Laboratory at the Brookhaven National Laboratory in New York. The rodents were then moved to Limoli’s lab at UCI.
Worryingly, the team found that the rodents had significant levels of brain inflammation six months after their exposure to the harmful particles. The damage to the rodents’ brains was equivalent to that seen in people who exhibit poor performance on behavioral tasks when testing for memory and learning skills.
Beyond this, the UCI researchers found that the radiation exposure impacted what’s called “fear extinction” – a process where the brain suppresses past stressful associations. What exactly does that mean? Well, think of someone who once nearly drowned but was eventually able to put that behind them and learn to enjoy the water again.
“Deficits in fear extinction could make you prone to anxiety, which could become problematic over the course of a three-year trip to and from Mars,” Limoli said.
Limoli’s study falls under NASA’s Human Research Program, which examines how the challenges of space travel could affect astronaut health.
The findings were in line with some other studies that looked into the impact of radiation treatments on the brains of cancer patients. Limoli said similar kinds of cognitive dysfunction are seen in brain cancer patients who have received high doses of photon-based radiation treatments.
Troubling for future missions to Mars, Limoli stressed that the amount of time it would take to send astronauts to the planet would be enough for these impairments to form. What about astronauts already in space? Limoli said that those working on the International Space Station, for instance, do not experience the same kind of assault of oncoming galactic cosmic rays due to the fact that they are still traveling within Earth’s protective magnetosphere.
Limoli said that there are feasible solutions to protect astronauts heading off to future missions on the Red Planet. Spacecrafts could incorporate better shielding. That being said, these charged particles would still penetrate a ship.
“There is really no escaping them,” he cautioned.
Right now, the research team is looking into possible drug compounds that could protect from this kind of radiation. Meanwhile NASA and private companies like SpaceX continue to develop plans and the necessary technology to launch humans to Mars in the coming decades.
