4Q Bodies in Space

1. What happens to the human body in space?

On Earth, gravity pulls fluid down to your feet, but in space the fluid goes up toward your head. This reversal of fluid position changes heart function, cardiovascular pressures, eye function, cerebrospinal fluid pressures, lymphatic function, lymphatic pressures, and many other things. Astronauts also lose bone, heart, and muscle mass. My research is on vision impairment and intracranial pressure syndrome.

2. What preventive measures are taken by astronauts to decrease health risks?

Drugs are available to counteract loss of bone mass. Astronauts exercise in space to maintain muscle mass. We don’t know how to minimize vision loss and that’s a big problem.

3. How do scientists simulate conditions that astronauts may experience?

There’s not an environment on Earth that produces similar conditions and you can’t run a clinical trial in space, so conducting experiments on astronaut health is extremely difficult. Scientists rely a lot on computer models to make predictions about how certain treatments will work. We need to develop these models for a wider range of conditions.

4. How did you get interested in astronaut health?

NASA became aware that just under half of long-duration astronauts suffer from vision impairment, but couldn’t discern who was at risk and who wasn’t. The vision problems are believed, in part, to be a result of alterations in fluid pressure—specifically cerebrospinal fluid and how it interacts with the eye. My expertise is in understanding the effects of pressure in the eye, so it was natural for me to become involved with this project.