Scientists have long been studying the impact of space on astronauts’ health. If people are going to colonize the planets of the solar system, it is necessary to carefully prepare them for a long flight, and this is not easy to do without medical knowledge. Most scientific studies are directed either to the study of the effects of radiation on the body or to psychological health, and little has been written about cognitive disorders. NASA experts tried to correct the situation. They conducted the largest study to date of astronauts’ cognitive abilities and identified a number of problems that could make it difficult to send human missions to other planets.

Long-term exposure to low gravity, cosmic radiation and disruption of the circadian rhythm have serious consequences for the health of astronauts, from loss of muscle mass to increased risk of heart disease. Researchers came to this conclusion after studying the mental and physical health of people in orbit for several years. However, the degree of cognitive decline that could occur during ISS flights or theoretical long-term space travel was poorly understood until recently.

A team of American neurophysiologists led by Sheena Dev from NASA’s Lyndon Johnson Space Center (Sheena Dev) examined the cognitive abilities of 25 astronauts during their six-month stay on the ISS. To be more precise, cognitive functions were assessed from 10 cognitive tests. Scientists presented the results of their scientific study in an article published in the journal Frontiers in Physiology.

Cognitive performance data were collected both on Earth and in space: pre-flight while on the ISS, and for 10 and 30 days after returning home.

For example, astronauts were asked to find patterns on a special grid to test abstract thinking, or to choose the moment to stop an inflating balloon before it burst to test risk-taking. After the tests, the authors of the study calculated speed and accuracy parameters, which reflect the deviation of cognitive abilities from the norm at different stages of the task.

Researchers found that astronauts needed more time to complete tests measuring information processing speed, visual working memory and sustained attention while on the ISS than on Earth. Additionally, towards the end of the flight, people’s risk appetite decreased. In other words, cognitive functions important for working in space were impaired for a while.

No widespread decline in cognitive abilities has been observed in astronauts. Some indicators, such as computing speed, returned to normal after returning to Earth. According to the authors of the article, indicators such as information processing speed, visual working memory, sustained attention, and risk taking may be most subject to changes in low Earth orbit and during long space flights. Experts need to pay attention to this when training astronauts for space missions.

“People will have to rely on themselves rather than automation as they may experience communication problems when they are away from home due to distance and signal delays. It is important to stay calm and make quick decisions. The situation will be difficult for a person who reacts slowly and is not able to understand such a situation very well,” explains psychologist Eliza Ferre ( Elisa Ferre ) from Birkbeck University of London (England).

Data on the cognitive decline that spaceflight can cause will be critical for planning future missions to other planets. But more information needs to be collected both on Earth and in space before scientists can build a complete picture of these changes.