When it comes to life on Earth, we're one of the most fragile species there is. But thanks to the rather perfect confluence of circumstances and cosmic events, we're mostly shielded from the dangers of space. Strong ultraviolet rays are kept out, our vital oxygen and water are kept in, and life continues blissfully. But what happens when we leave our own little planet in search of others? What protection do we have then?
For years, ever since the first word of space exploration was said, NASA has sponsored countless studies looking to investigate the short-term and long-term effects that space radiation has on the human body. To date we have seen that it can have devastating effects on biological tissue, and with only a short period of exposure serious malignancies like cancer can develop. But that's no longer the only fear of exploring deeper in space.
In a new study published this week in the journal Science Advances, professor of radiation oncology at UC Irvine, Charles Limoli says that even low doses of cosmic radiation can have drastic effects on the human brain. And with cosmic rays constantly bombarding the brain while outside of the protective layering of our Earth, serious brain damage causing cognitive and memory impairments could manifest in just a matter of months.
"This is the first study, in my opinion, that really ties a lot of loose ends together and provides a mechanism for what's going on to cause cognitive dysfunction" Limoli says.
To study the effects that cosmic radiation could have on human brains, Limoli and his team of researchers exposed young mice to small doses of common particles encountered in space. Then they explored three possible outcomes-behavior, brain structure, and the changes to neural and glial cells. As the cellular mischief of the radiation revealed itself, the team of researchers found that serious cognitive changes occurred and that permanent cellular changes to the shape and function of dendrites caused massive damage throughout the brain. And further worrisome was a discovery that the mice had also lost the ability for something else.
"The animals that we exposed lost curiosity" Limoli says. "They lost their tendency to explore novelty."
A problem for astronauts seeking new ventures in space-if they cannot remember what they're studying or the curiosity that drives science, then the mission is all a lost cause.