Astronaut Brains Shift in Space, Study Finds

A MIT-led study analyzed MRI scans from 26 astronauts and 24 non-astronauts, finding that extended spaceflight consistently shifts the brain backward and upward inside the skull and alters its pitch. Some changes persist for months after returning to Earth, and the brain regions linked to balance and spatial orientation are affected. The research, which also compared spaceflight data to a bed-rest “microgravity analog,” suggests broad neuroanatomical effects from microgravity but notes limitations like small sample sizes and variability in mission duration. The team calls for larger, longer studies to understand onset, evolution, and recovery of these brain shifts.