Space Reshapes Astronauts' Brains: Study Reveals Profound Structural Changes

• A new study in PNAS reveals long-duration space travel fundamentally reshapes the human brain, causing it to shift upwards and backwards within the skull.
• This displacement leads to significant "crowding" at the top of the head, stretching and compressing neural tissue.
• Research led by Dr Rachel Seidler of the University of Florida analyzed MRI data from 26 ISS astronauts, showing shifts up to 2.5 mm in the supplementary motor cortex for year-long missions.
• The structural distortion correlates with balance declines and sensory disorientation upon returning to Earth, with some changes persisting post-mission.
• Findings have critical implications for future long-duration missions like Mars, and suggest a link to Spaceflight-Associated Neuro-ocular Syndrome (SANS).

Why It Matters: Long-duration space travel causes significant, persistent structural reshaping of astronauts' brains, impacting health and future missions.