Validation of Centrifugation as a Countermeasure for Otolith Deconditioning During Spaceflight (Spin) - 12.03.13
Science Objectives for Everyone
The Validation of Centrifugation as a Countermeasure for Otolith Deconditioning During Spaceflight (Spin) investigates the effect on the reflexes that sense gravity and linear acceleration (otolith-ocular reflexes) and its effect on the autonomic nervous system. Particularly, this investigations focuses on these otolith-ocular reflexes and the correlation with the development of symptoms during upright standing such as changes in heart rate, blood pressure, and cerebral blood flow that can be relieved by sitting down, or orthostatic intolerance.
Science Results for Everyone
European Space Agency (ESA)Sponsoring Organization
Information PendingResearch Benefits
Information PendingISS Expedition Duration:
October 2007 - September 2012Expeditions Assigned
16,17,19/20,21/22,29/30,31/32Previous ISS Missions
Spin was first operated on ISS Expedition 16.
- The Validation of Centrifugation as a Countermeasure for Otolith Deconditioning During Spaceflight (Spin) experiment measures the inner-ear located otolith organs and how they mediate eye movements in the human body (otolith-ocular reflexes). Particularly, the eye movements of interest are ocular counter-rolling or OCR (a twisting of the eyes with head tilting due to gravity), spatial orientation of the vestibulo-ocular reflex or VOR (a normal reflex in which eye position compensates for head movement), and optokinetic nystagmus or OKN (rhythmic oscillating involuntary eye movements). These eye movements are measured in response to tilts of the gravito-inertial acceleration vector (GIA) during pre and post flight tangential centrifugation.
- Measurement of OCR, spatial orientation of the VOR, and the OKN is done pre- and post flight using static roll-tilt testing. Evaluation of pre and post flight orthostatic tolerance is done by monitoring heart rate, blood pressure, and fluid shifts during a standardized tilt test that was previously used for the STS-90 Neurolab mission. Segmental body impedance will be used to estimate fluid shifts and the stroke volume, or the amount of blood pumped out of a one ventricle of the heart on a single beat. From these measurements, the resistance offered by blood vessels to bloodflow, or vascular resistance, can be calculated and used as an estimate of the activation of the cardiovascular system related to this type of stress on the human body.
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 (centrifugation) 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.
Information PendingEarth Applications
Information PendingOperational Protocols
Buytaert KI, MacDougall HG, Moore ST, Clement G, Pattyn N, Migeotte PF, Migeotte PF, Wuyts FL. Validation of centrifugation as a countermeasure for otolith deconditioning during spaceflight: Preliminary data of the ESA SPIN study. Journal of Vestibular Research. 2013 January 1; 23(1): 23-31.
Ground Based Results Publications
Final check before centrifugation of the cosmonaut Youri Malenchenko seated on the VVIS in Star City (GCTC - Moskow).
+ View Larger Image