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Updated: Jul 31, 2026
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Video-oculography in Mice
Published on: July 19, 2012
Ocular counterrolling induced by centrifugation during orbital space flight
S T Moore1, G Clément, T Raphan
1Department of Neurology, Mount Sinai School of Medicine, Box 1135, 1 E 100th St., New York, NY 10029, USA. steven.moore@mssm.edu
Experimental Brain Research
|May 18, 2001
Summary
Artificial gravity via centrifugation during spaceflight maintained ocular counterrolling (OCR) magnitude, unlike previous studies. Intermittent artificial gravity may counteract vestibular system deconditioning in astronauts.
Area of Science:
- Neuroscience
- Space Physiology
- Vestibular System Research
Background:
- Astronauts experience vestibular system deconditioning during spaceflight due to microgravity.
- Ocular counterrolling (OCR) is a reflex mediated by the otolith organs, sensitive to gravitoinertial forces.
- Previous studies often show decreased OCR post-flight, indicating vestibular deconditioning.
Purpose of the Study:
- To investigate the effect of artificial gravity (centripetal acceleration) on ocular counterrolling (OCR) in astronauts.
- To determine if intermittent centrifugation can mitigate vestibular deconditioning during a 16-day space mission.
- To differentiate the contribution of interaural linear acceleration versus head dorsoventral acceleration to OCR.
Main Methods:
- Four astronauts underwent centrifugation (0.5g and 1g) on Earth and during the Neurolab (STS-90) mission.
- Subjects were exposed to interaural centripetal accelerations with varying orientations (ear-out, facing/back to motion).
- Binocular eye movements were measured in 3D using video techniques to quantify ocular counterrolling (OCR).
Main Results:
- On Earth, 1g centrifugation (1.4g total gravitoinertial acceleration) elicited a mean OCR of 5.7 degrees.
- In microgravity, in-flight centrifugation resulted in a 10% decrease in OCR magnitude (5.1 degrees).
- Post-flight OCR was not significantly different from pre-flight levels, and OCR magnitude was maintained throughout the mission.
Conclusions:
- Ocular counterrolling (OCR) is primarily driven by interaural linear acceleration.
- The increased OCR on Earth during centrifugation is partly due to head dorsoventral acceleration, absent in microgravity.
- Intermittent exposure to artificial gravity via centrifugation may serve as a countermeasure against otolith-ocular reflex deconditioning in space.
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