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Updated: Jul 14, 2026
09:46
MPI CyberMotion Simulator: Implementation of a Novel Motion Simulator to Investigate Multisensory Path Integration in Three Dimensions
Published on: May 10, 2012
Inverted immersion as a novel gravitoinertial environment
W T Norfleet1, A C Coats, M R Powell
1NASA/Johnson Space Center, Houston, TX, USA.
Aviation, Space, and Environmental Medicine
|September 1, 1995
Summary
Inverted immersion (II) causes significant motion sickness (MS) and postural instability. This novel environment is more provocative of MS symptoms than upright immersion (UI).
Area of Science:
- Physiology
- Human Factors Engineering
- Vestibular Science
Background:
- Inverted immersion (II) alters the gravity vector relative to vestibular organs, creating a novel gravitoinertial environment.
- While extrathoracic fluid dynamics are similar to upright immersion (UI), the altered orientation is hypothesized to induce motion sickness (MS).
Purpose of the Study:
- To determine if inverted immersion (II) is more provocative of motion sickness (MS) than upright immersion (UI).
- To assess postural stability following II compared to UI.
Main Methods:
- Nine subjects underwent both II and UI conditions wearing SCUBA gear.
- Participants performed tasks including puzzle assembly, head movements, and ambulation for up to 3 hours or until nausea onset.
- Postural stability was assessed post-dive, and pre-dive questionnaires evaluated MS susceptibility.
Main Results:
- Seven of nine subjects terminated the II trial due to MS, compared to none during UI (p < 0.025).
- Postural stability was significantly reduced after II compared to UI (p < 0.05).
- Pre-dive MS susceptibility did not predict II-induced MS.
Conclusions:
- Inverted immersion (II) is a potent stimulus for inducing motion sickness (MS).
- II also leads to significant postural instability.
- Further research into the mechanisms and countermeasures for II-induced MS is warranted.
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