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Validation of Centrifugation as a Countermeasure for Otolith Deconditioning During Spaceflight (Spin)
Principal Investigator
Research Area:
Species Studied
Scientific Name: Homo sapiens Species: Human

The Validation of Centrifugation as a Countermeasure for Otolith Deconditioning During Spaceflight (Spin) experiment will investigate the effect of microgravity on otolith-ocular reflexes and autonomic function to correlate the otolith-ocular reflex on orthostatic tolerance. It will also study the effect of microgravity on subjective perception of verticality.

In contrast to previous studies, postflight measures of both otolith-ocular function and orthostatic tolerance were unimpaired in four payload crewmembers exposed to artificial gravity generated by inflight centrifugation during the Neurolab (STS-90) mission. The aim of the SPIN study is to obtain control measures of otolith and orthostatic function following long-duration missions, utilizing the centrifugation and autonomic testing techniques developed for the Neurolab mission, from crewmembers who have not been exposed to in-flight centrifugation. This will enable a direct comparison with data obtained from the Neurolab crew.

When otolith-ocular deficits are observed in the crewmembers that are not exposed to intermittent artificial gravity in flight, this would support the hypothesis that in-flight centripetal acceleration is a countermeasure for otolith deconditioning. Furthermore, a correlation between postflight otolith deconditioning and orthostatic intolerance would establish an otolithic basis for deficits in sympathetic outflow related to orthostatic stress.

These would be highly significant findings for future long-duration space missions, where providing an artificial gravity countermeasure for otolith and orthostatic deconditioning may prove critical to the well being of the crew, particularly during emergency egress.

These findings are also relevant to studies of imbalance and orthostatic intolerance on Earth. Many of the postural and locomotor deficits observed in astronauts postflight are similar to those seen in patients with vestibular disease, and findings from this study may shed light on the otolithic basis for these conditions.

Orthostatic intolerance

Data Information
Data Availability
Archiving in progress. Data is not yet available for this experiment.

Orthostatic tolerance
Otolith-ocular reflexes
Subjective perception of verticality

Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
Expedition 16 10/10/2007 04/19/2008 192 days
Expedition 17 04/08/2008 10/23/2008 198 days
Expedition 19 03/26/2009 10/11/2009 199 days
Expedition 20 05/27/2009 10/11/2009 137 days
Expedition 21 10/11/2009 12/01/2009 51 days

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Jessica Keune
Institutional Support
European Space Agency (ESA)