Deep-space radiation may impair astronauts’ cognitive function: study

Irvine, CA — Astronauts traveling to Mars and beyond in the future could encounter radiation that disrupts brain function, results of a recent study out of the University of California, Irvine suggest.

Researchers looked at the impact of low-dose neutron radiation – simulating the kind in deep space – on mice. Past studies have used acute radiation doses that are many times greater than those found in space.

The cumulative effect of this radiation on the mice resulted in “severe impairments in learning and memory, and the emergence of distress behaviors,” the study abstract states. “Behavioral analyses showed an alarming increase in risk associated with these realistic simulations, revealing for the first time some unexpected potential problems associated with deep-space travel on all levels of neurological function.”

The researchers predict that approximately 1 out of 3 astronauts will have memory problems during missions to Mars and about 1 out of 5 will “experience anxiety-like behavior.”

A pair of researchers not involved in the study, however, express skepticism over the results in an Aug. 7 report published online by Inside Science.

“There is no way an astronaut would be exposed to this neutron energy source or the equivalent dose used,” Francis Cucinotta, a health physicist at the University of Nevada, Las Vegas, said in the report.

Jeff Chancellor, a physicist at Louisiana State University, took issue with the researchers’ use of neutrons as a radiation source. “They are claiming that these fast neutrons are a viable surrogate because it’s a low dose, but it’s still not the same.”

Two of the study’s authors, Janet Baulch and Charles Limoli from UC Irvine, detailed their work in an Aug. 5 article on theconversation.com.

“Our work is just one study and the results must be replicated, but it does raise the sobering possibility that galactic cosmic radiation exposure may represent a significant obstacle to deep-space travel,” they wrote. “As with other technological challenges, though, we hope researchers will find a solution.”

The study was published online Aug. 5 in eNeuro, an open-access journal of the Society for Neuroscience.