ABSTRACT
This chapter describes the symptomatology of the maladaptation syndrome commonly called motion sickness (MS) (Irwin, 1881), that is, the adverse symptoms and readily observable signs that are associated with exposure to real and/or apparent (e.g., visual) motion. MS incidence, observable clinical signs, and subjective symptoms of MS are described in detail (Sections 23.2 and 23.3), as well as the typical temporal progression of signs and symptoms (Section 23.4). Related syndromes (in Section 23.5) that do not necessarily involve nausea and vomiting but may pose a health or safety risk are discussed: these include the sopite syndrome, loss of dynamic visual acuity during head or body motion, and postural disequilibrium caused by real or apparent motion and their aftereffects. Situations conducive of these various problems are discussed as well. For example, the evidence to date indicates that many virtual environments (VEs) are capable of producing signi˜cant decrements in well-being (Sections 23.2.5 through 23.2.7; Sections 23.6 and 23.7). Careful assessment and correction of human factors problems in VEs is recommended to minimize user concerns about comfort, health, and safety.
