How spaceflight changes the brain: Study on 15 astronauts reveals micro-gravity alters white matter and causes brain to float higher in the skull
- Researchers studied brain scans of 15 astronauts before and after space flight
- They detected changes in the white matter areas that control movement, senses
- While many changes corrected themselves in weeks, others could take months
A new study supported by NASA has shed worrying light on the effects of space travel on the human brain.
Brain scans of astronauts from before and after spaceflight revealed changes typically associated with long term processes such as aging, including deterioration in areas responsible for movement and the processing of sensory information.
The results, however, also suggest an astronaut’s brain may be able to adapt to these changes over time.
A new study supported by NASA has shed worrying light on the effects of space travel on the human brain. Brain scans of astronauts from before and after spaceflight revealed changes typically associated with long term processes such as aging. File photo
WHY DO YOU GET TALLER IN SPACE?
Astronauts can grow up to three inches (seven cm) taller in space, because of how microgravity affects the human body.
Imagine that the vertebrae in your back form a giant spring.
Pushing down on the spring keeps it coiled tightly.
When the force is released, the spring stretches out.
In the same way, the spine elongates by up to three per cent while humans travel in space.
There is less gravity pushing down on the vertebrae, so they can stretch out.
Stretching of the spine also happens every night to some degree as, when you lie down, gravity isn’t pushing down on your vertebrae.
‘We know that fluid shifts toward the head in space,’ said Rachel Seidler, a professor with the College of Health and Human Performance at the University of Florida.
‘When you see photos and video of astronauts, their faces often look puffy, because gravity isn’t pulling fluids down into the body.’
These gravitational effects aren’t just worn on the surface – according to the new study, spaceflight directly affects the brain’s white matter in the regions that control movement and process sensory information.
And, the team found that spaceflight causes fluid around the brain to pool at the base of the cerebrum, as if the brain is ‘floating higher’ in the skull.
This could play a key role in a condition called Spaceflight Associated Neuro-Ocular Syndrome, which causes visual changes and flattening in the back of the eye.
‘It could be slower fluid turnover, it could be pressure on the optic nerve or that the brain is sort of tugging on the optic nerve because it’s floating higher in the skull,’ Seidler said.
But, the researchers say, the white matter problems don’t appear to be permanent.
Typically, these changes fix themselves in a matter of weeks after the astronauts return to Earth.
Some changes, however, could last months.
Moving forward, the team plans to include scans from six months after spaceflight as well.
The study revealed changes including deterioration in areas responsible for movement and the processing of sensory information. The results, however, also suggest an astronaut’s brain may be able to adapt to these changes over time. File photo
The findings aren’t just important for astronauts, but for future space tourists as well, especially as inactive lifestyles continue to be common.
Upon returning to Earth, an astronaut’s body isn’t sending as much sensory input to the brain, the researchers note.
‘We have an increasingly sedentary lifestyle,’ Seidler notes.
‘It’s not the same as the effects on limbs in space, but if we’re laying around and not using our bodies, could the integrity of white matter pathways in the brain be affected?
‘Another reason for an active lifestyle.’