Motion sickness. Part I. Development of of a model for predicting motion sickness incidence

This is the first part of a two-part paper in which a new theoretical approach for predicting motion sickness is shown and experimentally validated. In the present paper, two models are proposed, both based on sensory conflict theory and in particular on subjective vertical conflict theory. They analyse motion sickness by evaluating the motion sickness incidence index (MSI). They allow the analysis of various typologies of vehicles discriminating among the various vehicle configurations, among the positions that the passenger and/or passenger’s body can assume. These two models allow to highlight leakage, adaptation and anticipation. The first model (UNIPG) is a 3D extension of a previous authors’ model based only on vestibular stimuli. The second model (UNIPGSeMo) introduces the contribution of the visual system to the perception of motion as well as the contribution to the conflict of that among the senses (inter-sensory conflict) never yet formalised in motion sickness prediction models.