The conversationMar 22, 2021 12:39:34 PM
Human space missions to Mars are the next big leap in space exploration, with NASA targeting the 2030s as the appropriate timeframe for inclusion the first people there. However, getting on a trip to Mars is nothing like a flight to New York. Space is an extremely hostile environment for human life – from the lack of gravity and harmful radiation to isolation and the lack of day and night. Space missions to Mars will be much more physically and mentally demanding than the journeys we have made during 60 years of human space exploration. A flight to Mars and back will take approximately 14 months, while the actual fact-finding mission will take at least three years. A sustained high level of cognitive performance and effective teamwork are prerequisites for the safe and successful outcome of these missions.
Exposure to “microgravity” leads to dramatic changes in the human body, including changes in the cardiovascular, musculoskeletal and nervous systems.
But a new study published in Frontiers of Physiologyfound that the lack of gravity on such missions can negatively affect astronauts’ cognitive skills and emotional understanding.
It has been clear since the first space missions that exposure to “microgravity” (weightlessness) leads to this dramatic changes in the human body. This includes changes in the cardiovascular, musculoskeletal and nervous systems. On earth, we recognize gravity through our sight and various organs, including those in the inner ear. When our head is upright, little stones in our ears – the vestibular otoliths – are perfectly balanced on a viscous liquid. But when we move our head, gravity moves the liquid and this triggers a signal to the brain that our head has changed position. This process no longer works in space travel.
Space travel can even adversely alter the anatomy of astronauts’ brains. Structural brain changes have been observed in astronauts after returning from the International Space Station (ISS). This includes the brain physically Upward movement within the skull and reduced connectivity between areas on the layer of the brain, the cortex and those inside.
How these changes affect behavior is not fully understood. But scientists are making progress. We know astronauts can suffer Disorientation, illusions of perception, imbalance and motion sickness. However, such findings are often based on small samples.
Simulate microgravity
The new NASA-sponsored study examined the effects of microgravity on cognitive performance. But instead of sending their 24 study participants into space, they sent them to bed. That’s because the effects of a particular type of bed rest are analogous to the effects of microgravity – we use them a lot in research. When we are upright, our body and vestibular otoliths are in the same direction as gravity, while when we are lying down, they are orthogonal (at right angles).
The study participants therefore had to lie on their back at an angle of 6 ° for almost two months, with the head lower than the body, without changing position. They were asked to regularly perform a series of astronaut cognitive tasks relevant to space travel to assess their spatial orientation, memory, risk behavior, and emotional understanding of others.
The results showed a small but reliable slowdown in cognitive speed for tasks involving sensory and motor skills. This seems to be coherent reported changes in the density of the brain tissue over the “sensorimotor cortices”, the primary sensory and motor areas of the brain that help process sensory inputs and movements that are observed after space travel. Participants also had difficulty reading emotions when looking at people’s faces.
Adapting to changes in gravity takes time and effort. While the performance of most cognitive tasks decreased initially, they remained unchanged after about 60 days during the course of the experiment. But the ability to recognize emotions continued to deteriorate. In fact, participants were biased towards negative emotions – they were more likely to identify others’ facial expressions as angry and less likely to interpret them as happy or neutral.
This is an important finding. Astronauts’ ability to think sharply and quickly is critical to a space mission. This also applies to the ability to correctly “read” the other’s emotional expressions, as they have to spend a lot of time in a confined space. Space agencies should therefore consider appropriate pre-flight psychological training and in-flight psychological support to minimize this risk.
Recent advances and investments in missile technology usher in a new and exciting age in space exploration. Microgravity can be deeply troubling and can affect performance levels in many ways. With a view to human missions to Mars in space, an urgent research goal is to gain better insight into the effects of microgravity on cognitive performance and emotional health, and to develop appropriate medical and psychological support for space travel.
Elisa Raffaella Ferrè, Lecturer, Department of Psychology, Royal Holloway
This article is republished by The Conversation under a Creative Commons license. Read the original article.
