title: Adaptation to vection-induced symptoms of motion sickness.
abstract: The visual-vestibular-proprioceptive sensory mismatch of vection provokes motion sickness in approximately 60% of healthy subjects. Approximately 60% of astronauts experience motion sickness in microgravity where vestibular/otolith function is altered. The purpose of this study was to determine the extent to which symptoms of motion sickness and tachygastria, an abnormal 4-9 cpm rhythm of the stomach, decrease or adapt during three repeated exposures to a rotating circular vection drum. Subjects sat in the drum for 45 min: 15 min baseline, 15 min drum rotation at 60 degrees.s-1, and 15 min recovery. Gastric myoelectric activity was continuously recorded with the electrogastrogram (EGG). Symptom reports were obtained during rotation. In Experiment I, 10 subjects were exposed to the drum 3 times with intersession intervals of 4-24 d. They failed to show adaptation based on subjective reports and all showed tachygastria. In Experiment II, 14 new subjects were exposed to the drum 3 times with intersession intervals of 48 h. The group experienced a reduction in symptoms and tachygastria with repeated exposure to the drum. Thus, symptomatic and physiological improvement occurred after training in subjects susceptible to vection-induced motion sickness. Preflight adaptation to visual-vestibular sensory mismatch may reduce motion sickness experienced in the environment of microgravity.
authors.affiliation: Department of Psychology, Pennsylvania State University, University Park, PA 16802.
authors.forename: R M
authors.initials: RM
authors.lastname: Stern
authors.forename: S Q
authors.initials: SQ
authors.lastname: Hu
authors.forename: M W
authors.initials: MW
authors.lastname: Vasey
authors.forename: K L
authors.initials: KL
authors.lastname: Koch
mesh_terms: D000222:Adaptation, Physiological; D000293:Adolescent; D000328:Adult; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D009041:Motion Sickness / Q000209:etiology / Q000503:physiopathology*; D012399:Rotation / Q000009:adverse effects; D013270:Stomach / Q000502:physiology*; D013997:Time Factors