The Impact of Space Travel on Astronauts' Brains: New Findings.

Spaceflights lasting six months or longer take a toll on the brains of astronauts, and crew members may need to wait at least three years before returning to space, according to new research. Scientists compared the brain scans of 30 astronauts taken before spaceflights lasting two weeks, six months or a year with scans taken after they returned to Earth. The scans revealed that the ventricles, or cavities within the brain that are filled with cerebrospinal fluid, expanded significantly within the brains of astronauts who went to the International Space Station on missions lasting at least six months.