The adaptation in the vestibular system will be assessed by comparing the perception of motion against the real movement of the body. To this end, the astronaut will be asked to fill in a short questionnaire every day during the spaceflight, wherein he reports his motion sensation as a result of head movements around the three principal axes. Head movements are important in the experiment as the inner ear is the location of the sensory organs of the vestibular system.
The astronaut will also be questioned on whether he experiences any discomfort regarding space adaptation syndrome (SAS), commonly known as `space sickness', caused by their daily activities. A second objective of the Motion Perception experiment is to correlate an astronaut's susceptibility to space sickness with a susceptibility to sickness induced by centrifugation. Sickness induced by centrifugation is a condition with similarities to space sickness. A pre-flight ground experiment will be performed wherein the astronaut's susceptibility to sickness induced by centrifugation is assessed by exposing him to hypergravity (approximately 3g) in a centrifuge.
Results can be found in the cited publications below.
|Mission||Launch/Start Date||Landing/End Date||Duration|
|Expedition 10||10/13/2004||04/24/2005||193 days|
|Expedition 11||04/14/2005||10/10/2005||179 days|
|Expedition 12||09/30/2005||04/30/2006||180 days|
|Expedition 16||10/10/2007||04/19/2008||192 days|
|Expedition 18||10/12/2008||04/17/2009||187 days|
|Expedition 19||03/26/2009||10/11/2009||199 days|
|Expedition 20||05/27/2009||10/11/2009||137 days|
|Expedition 8||10/18/2003||04/29/2004||195 days|
|Expedition 9||04/18/2004||10/23/2004||188 days|