Venue: BBS
Defense in french
Tess Bonnard
INCIA
Title
Vestibular integration in modified gravity and motion sickness
Abstract
Motion sickness arises from conflicts between sensory signals, particularly those originating from the vestibular system. However, its underlying mechanisms remain poorly understood, especially in the case of space motion sickness, which affects astronauts during exposure to weightlessness.
This thesis compares space motion sickness, reproduced during parabolic flights, with terrestrial motion sickness induced by virtual reality. It investigates the associated sensory conflicts and physiological responses.
Vestibular perception of rotational movements is impaired in weightlessness, whereas the perception of translational movements remains accurate. In the presence of sensory conflict, the sensory input signaling motion appears to be weighted more strongly than the others during the integration and comparison of sensory signals. Sleep quality influences susceptibility to space motion sickness, and facial colorimetry emerges as an objective indicator of symptom severity.
These findings contribute to a better understanding of the mechanisms underlying motion sickness and provide new perspectives for the development of preventive strategies.
Publications
- Bonnard, T., Doat, E., Cazalets, J., Guehl, D., & Guillaud, E. (2025). Visual and vestibular reweighting after cyber‐ and space‐sickness. Experimental Physiology, 111(1), 240‑256. https://doi.org/10.1113/ep092966
- Bonnard, T., Morello, A., Doat, E., Cazalets, J., Guehl, D., & Guillaud, E. (2026). Resilience of otolithic reflex to gravitational changes. Npj Microgravity, 12(1). https://doi.org/10.1038/s41526-026-00599-9
- Bonnard, T., Araka, L., Reina, A. S., Van Berkel, J., Morvan, C., Morgat, C., Guehl, D., Guillaud, E., & Altena, E. (2026). Sleep’s influence on susceptibility to motion sickness in parabolic flights and virtual reality : An exploratory study. Journal Of Vestibular Research, 9574271261474571. https://doi.org/10.1177/09574271261474571
- Bonnard, T., Doat, E., Cazalets, J., Morgat, C., Guehl, D., & Guillaud, E. (2026). Turning green in microgravity : facial color changes as best physiological indicator of space sickness. bioRxiv (Cold Spring Harbor Laboratory). https://doi.org/10.64898/2026.03.06.708504
- Bonnard, T., Doat, E., Guehl, D., & Guillaud, E. (2026). Swung and spun in weightlessness : Evidence of immediate canalar underdetection of rotations in parabolic flight. bioRxiv (Cold Spring Harbor Laboratory). https://doi.org/10.64898/2026.06.30.735470
Jury
- M. Etienne Guillaud – CNRS – Directeur de thèse
- Mme Gaelle Quark – Université de Caen – Rapporteure
- M. Lionel Bringoux – Université Aix Marseille – Rapporteur
- Mme Guillemette Gauquelin-Koch – Centre national d’études spatiales (CNES) – Examinatrice
- Mme Valérie Franco-Vidal – Centre universitaire hospitalier de Bordeaux – Examinatrice
- M. Jordan Navarro – Université Lumière Lyon 2 – Examinateur