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NASA NTRS · 20040173089

Motor function in microgravity: movement in weightlessness

Lackner, J. R.·DiZio, P.
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Abstract

Microgravity provides unique, though experimentally challenging, opportunities to study motor control. A traditional research focus has been the effects of linear acceleration on vestibular responses to angular acceleration. Evidence is accumulating that the high-frequency vestibulo-ocular reflex (VOR) is not affected by transitions from a 1 g linear force field to microgravity (<1 g); however, it appears that the three-dimensional organization of the VOR is dependent on gravitoinertial force levels. Some of the observed effects of microgravity on head and arm movement control appear to depend on the previously undetected inputs of cervical and brachial proprioception, which change almost immediately in response to alterations in background force levels. Recent studies of post-flight disturbances of posture and locomotion are revealing sensorimotor mechanisms that adjust over periods ranging from hours to weeks.

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NASA Program FlightFlight ExperimentReviewNASA Program Space Physiology and CountermeasuresNASA Discipline NeuroscienceNASA Discipline Number 00-00short durationNASA Discipline Number 16-10STS Shuttle ProjectParabolic FlightNon-NASA CentermannedReview, TutorialWeightlessness/adverse effectsMotor Skills/physiologyMovement/physiologySupport, U.S. Gov't, Non-P.H.SHumanAnimalsReflex/physiology

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Lackner, J. R., DiZio, P.. 1996-12-01. Motor function in microgravity: movement in weightlessness. https://ntrs.nasa.gov/citations/20040173089

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