New research has implications for crew safety in space and could give clues about how aging affects the balance systems of people on Earth.
horges other. We addressed the question of whether body posture influences humans' perception of self-motion and distance. They found that the same amount of optical flow can elicit the sensation of traveling farther when lying on one's back and when sitting upright; that is, optical flow We found evidence that it is more effective in eliciting the sensation of movement. This constitutes evidence that visual and nonvisual cues are at least partially integrated, even when self-movement is presented only visually. However, we found no significant differences in performance in microgravity on Earth and on the ISS, suggesting that vestibular stimulation is not important, if any, in estimating visually presented self-motion.
The study's lead author, Professor Lawrence Harris from the University of York, said: “The perception of gravity has been repeatedly shown to influence perceptual abilities.”
“The most profound way to study the effects of gravity is to remove it. That's why we brought our research into space.”
“We have had a steady presence in space for nearly a quarter of a century, but our efforts in space are ever-increasing as we plan to return to the moon and beyond, ensuring health and safety. It is becoming increasingly important to answer questions about
“Based on our findings, it appears that humans are surprisingly able to use vision to adequately compensate for the lack of Earth's normal environment.
For the study, Professor Harris and his colleagues surveyed more than a dozen astronauts aboard the International Space Station (ISS), which orbits about 400 kilometers above the Earth's surface.
“Here, Earth's gravity is almost canceled out by the centrifugal force generated by the station's orbit. In the resulting microgravity, the movement of people becomes close to flight,” Professor Harris said.
“People had previously reported anecdotally that they felt like they were traveling faster or farther than they were actually in space, so this actually motivated us to record this.”
The authors compared the performance of 12 astronauts (six men and six women) before, during, and after a year-long mission to the space station and found out how far they traveled. I discovered that my sense of what I had done was almost intact.
Space missions were hectic endeavors, and it took several days for researchers to make contact with the astronauts after arriving at the space station.
“Our study may not have captured early adaptations that may have occurred during the first few days. Because whatever adaptations occur, they occur very quickly. This remains a good news message,” Professor Harris said.
Space missions are not without risks. Because the ISS orbits around the Earth, small objects can occasionally collide with it and enter the ship, where astronauts must move to safety.
“During the experiment, the ISS had to take many evasive maneuvers,” Professor Harris said.
“Astronauts need to be able to get to safety or escape through a hatch on the ISS in an emergency. So to see that they were actually able to do this with great precision was very exciting. I felt relieved.”
“Our research shows that exposure to microgravity mimics the aging process primarily at a physiological level, including bone and muscle wasting, changes in hormonal function, and increased susceptibility to infections. However, this paper found that self-movement was largely unaffected, suggesting a balance problem.''The problem, which often comes from old age, may have nothing to do with the vestibular system. ”
“This suggests that the mechanisms of movement perception in older people should be relatively unaffected, and that the problems associated with falls are probably more to do with this than in terms of perception of distance traveled. How can they translate that into a balance reflex? ”
of study Published in npj magazine microgravity.
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B. Horges other. 2024. Effects of long-term exposure to microgravity and body orientation relative to gravity on perceived distance traveled. NPJ microgravity 10, 28; doi: 10.1038/s41526-024-00376-6
Source: www.sci.news
