title: The critical role of velocity storage in production of motion sickness.
abstract: We propose that motion sickness is mediated through the orientation properties of velocity storage in the vestibular system that tend to align eye velocity produced by the angular vestibulo-ocular reflex (aVOR) with gravito-inertial acceleration (GIA). (GIA is the sum of the linear accelerations acting on the head. In the absence of translational accelerations, gravity is the GIA.) We further postulate that motion sickness produced by cross-coupled vestibular stimulation can be characterized by a metric composed of the disparity between the axis of eye rotation and the GIA, the strength of the response to angular motion, and the response duration, as determined by the central vestibular time constant, that is, by the time constant of velocity storage. The nodulus and uvula of the vestibulocerebellum are likely to be the central sites where the disparity is sensed, where the vestibular time constants are habituated, and where links are made to the autonomic system to produce the symptoms and signs.
authors.affiliation: Department of Neurology, Mount Sinai School of Medicine, New York, New York 10029, USA. bernard.cohen@mssm.edu
authors.forename: Bernard
authors.initials: B
authors.lastname: Cohen
authors.forename: Mingjia
authors.initials: M
authors.lastname: Dai
authors.forename: Theodore
authors.initials: T
authors.lastname: Raphan
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004244:Dizziness / Q000503:physiopathology; D004311:Double-Blind Method; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D019416:Head Movements / Q000502:physiology*; D006634:Histamine H1 Antagonists / Q000008:administration & dosage; D006801:Humans; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009041:Motion Sickness / Q000503:physiopathology* / Q000517:prevention & control; D009325:Nausea / Q000503:physiopathology; D009760:Nystagmus, Physiologic / Q000502:physiology; D011398:Promethazine / Q000008:administration & dosage; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology*; D012399:Rotation
chemical_list: D006634:Histamine H1 Antagonists; D011398:Promethazine