Astronauts return from space as changed individuals: something unusual happens to their brains during their missions.

Researchers have examined the behavior of 25 astronauts who spent six months aboard the International Space Station (ISS) over the past few years. It was found that astronauts require more time to complete certain tasks related to data processing speed, working memory, and attention during their time in space. These findings raise concerns about the potential effects of future missions to the Moon and Mars on astronauts' brains. The study has been published in the journal Frontiers in Physiology, as reported by Gizmodo.

Scientists have long been aware of the challenges astronauts face in space, including exposure to cosmic radiation, microgravity, loss of bone density, and sleep difficulties. Now, they have discovered that the cognitive functioning of astronauts may also change in space, manifested as slower information processing.

The authors of the study assessed the cognitive abilities of 25 astronauts through a series of tests conducted before their flight to the ISS, during their six-month stay on the station, and after their return to Earth. Each test measured data processing speed and accuracy, comparing the astronauts' performance across different time periods.

The results revealed that astronauts responded more slowly to tasks designed to evaluate data processing speed, working memory, and attention while in space compared to on Earth. However, their accuracy levels remained intact. It was also found that the changes in cognitive behavior did not persist after their return to Earth.

Moreover, researchers did not find evidence of significant brain damage or permanent cognitive impairments. However, they could not identify the exact cause of the changes observed in the astronauts' brains.

Scientists believe that stress experienced by individuals in space might be a possible reason for these changes. According to the study's authors, even on Earth, data processing speed, working memory, and attention can temporarily fluctuate when a person is under stress.

While researchers are well aware of how prolonged space travel can negatively impact physical health, cognitive behavior in astronauts has been studied less extensively, though there are signs that space may also affect human brain function.

NASA is preparing to return astronauts to the Moon in the near future and then send the first humans to Mars. Given the study's findings, such extended journeys in space could have a more adverse impact on astronauts' conditions than previously thought.