By: Renee Jin

As an astronaut goes into space, their brain’s fluid-filled chambers expand. This expansion helps them adapt to the low gravity and it can take up to 3 years for the chambers to return back to normal.

How does this happen? The astronaut’s head slowly builds up with fluid because of the low gravity. Four ventricle-shaped compartments in the brain also accumulate extra fluid. Liquid that cushions the brain and flushes out cellular waste is contained within these chambers. These ventricles are frequently enlarged when astronauts return to Earth.

Rachael Seidler is someone who explores the adaptation of the human body to space. Seidler and her co-workers wanted to look into this deeper.

They compared what the brains of astronauts looked like before and after the mission and did MRI scans on their brains. Soon, the researchers began to see that, the more time you spend in space, the more your brain expands.

The study Seidler did answered many questions, and helped them understand what happens to your brain in space. “I’m glad that the [study] authors took the first step and are looking at this question,” says Donna Roberts, a brain-imaging specialist. “There are so many variables that could play into the brain changes that we’re seeing, It’s hard to sort them out.”