A team of researchers working at multiple facilities in the San Francisco
area has found that male mice exposed to radiation similar to that
encountered by humans on long space missions experienced problems with
spatial learning several months later. In their paper published in the
journal Science Advances, the group describes their simulations, how it
impacted the mice and the way they found to prevent adverse effects from
happening.
If humans are to colonize the moon or travel to Mars, scientists are going
to have to find a way to protect them from galactic cosmic radiation (GCR).
Some research has shown that it can have a negative impact on the central
nervous system. In this new effort, the researchers exposed lab mice to
conditions similar to those encountered by astronauts in deep space and then
tested them over time to find out what the radiation might have done to
their brains. In one of the tests, the researchers taught the mice to find a
platform hidden under opaque water using instructions given by the
researchers prior to GCR exposure and then tested them later on how well
they did with it. The test is a standard means of testing changes to spatial
learning over time.
The results showed that the male mice made more mistakes than the control
mice after their exposure but the female mice did not. More testing showed
that the impairment was likely due to activation of the immune system in the
brain. In other tests, the researchers did not find any evidence of an
increase in anxiety, problems with recognition memory or social ability. But
they did find that if they fed the mice a diet of food designed to deplete
microglia (immune cells in the brain) prior to their exposure to GCR, they
did not experience any spatial learning impairment. And they also found a
biomarker associated with the mice that were more likely to be negatively
impacted by such exposure—one that could one day be used to determine which
astronauts might be more or less susceptible to problems associated with GCR
exposure.
Reference:
Karen Krukowski et al, The impact of deep space radiation on cognitive
performance: From biological sex to biomarkers to countermeasures, Science
Advances (2021).
DOI: 10.1126/sciadv.abg6702
Tags:
Space & Astrophysics