Although the prospect of exploring space may just be too much for some people, astronauts just can’t get enough of it. The trouble is that as well as the excitement that deep space travel brings, there is also a high risk of astronauts causing serious damage to their brains as high-energy cosmic rays whizz through the craft and into their bodies.
A new study examined the effects that space-like radiation had on rodents. The results showed there to be significant brain damage and cognitive problems six months after being exposed to the radiation. This suggests that astronauts could endure memory problems, impaired judgment, and anxiety as a result of space radiation.
Charles Limoli is a neurobiologist at the University of California, and he says, “I do not think that during the course of a trip to Mars and back the astronauts will come back with anything remotely similar to full-blown Alzheimer’s. But more mild changes, more subtle changes – they would still be concerning, given the level of autonomy astronauts operate under and the amount of work they have to do.”
During the research, mice appeared to be less interested in new toys or toys in new locations once they’d been exposed to the radiation while rats became less flexible when responding to environmental changes. Both became more anxious and preferred to remain sheltered rather than be out in the open.
When Limoli and colleagues investigated the brain damage that may underlie these problems, hey found the neuron’s dendrites had a lot fewer spines than normal, and because the spines help pass signals between neurons, any damage to them will affect learning and memory. “When we look at those animals that perform the poorest on a given behavioral task, those animals show the largest reductions in these dendritic spines,” explains Limoli. Lasting inflammation was also found in the rodent’s brains.
During the research, none of the animals showed any signs of recovery, which surprised the researchers. But evidence suggests that these problems will, in fact, continue to linger. Limoli advises, “The actual time that these animals are irradiated here on Earth….is a matter of minutes, and we see changes now that last out to a year, which is astounding.” In humans, it could be months before these symptoms became apparent and until astronauts set off on a deep space mission, we can’t be sure exactly how the body will react to galactic cosmic rays.
Next, Limoli and team will try to find out which regions of the brain are the most vulnerable to the radiation. Drugs are also being made that could help protect the brain against exposure to or recovery from it. Limoli comments, “I don’t think this means we’re not going into space, but if we know what’s out there, we can prepare to deal with it much better.”
More News to Read
