Who knew spaceflight felt like 5 milliamps of electricity behind your ears? Apparently, that's all it takes to trick the brain into simulating similar sensorimotor disturbances that an astronaut would experience during, say, reentry.
The Galvanic vestibular stimulation (or GVS) system, created by Dr. Steven Moore of the National Space Biomedical Research Institute, is especially useful during training as it allows astronauts to prepare for the disorientation during a mission. Reentry is an incredibly disorienting time for astronauts as the body is trying to adjust from the near weightlessness of orbit to the regular ol' forces exerted on us planet-side.
While piloting a shuttle in a simulator, for instance, several astronauts brought their craft down in textbook fashion, keeping the shuttle at a safe 204 knots. Using the GVS system while performing the same maneuver, however, the pilots became disoriented and drifted dangerously toward 210 knots, all the while experiencing difficulty angling their craft correctly.
It all sounds horrible, sure, and yet I want to slap some GVS electrodes behind my ears and pretend my couch is a space shuttle.
Here's what an astronaut looks like all strapped in and wired up (click if you'd like to see it larger):