title: Ground-based training for the stimulus rearrangement encountered during spaceflight.
abstract: Approximately 65-70% of the crew members now experience motion sickness of some degree during the first 72 h of orbital flight on the Space Shuttle. Lack of congruence among signals from spatial orientation systems leads to sensory conflict, which appears to be the basic cause of space motion sickness. A project to develop training devices and procedures to preadapt astronauts to the stimulus rearrangements of microgravity is currently being pursued. The preflight adaptation trainers (PATs) are intended to: demonstrate sensory phenomena likely to be experienced in flight, allow astronauts to train preflight in an altered sensory environment, alter sensory-motor reflexes, and alleviate or shorten the duration of space motion sickness. Four part-task PATs are anticipated. The trainers are designed to evoke two adaptation processes, sensory compensation and sensory reinterpretation, which are necessary to maintain spatial orientation in a weightless environment. Recent investigations using one of the trainers indicate that self-motion perception of linear translation is enhanced when body tilt is combined with visual surround translation, and that a 270 degrees phase angle relationship between tilt and surround motion produces maximum translation perception.
authors.affiliation: Space Biomedical Research Institute, Johnson Space Center, Houston, Texas.
authors.forename: M F
authors.initials: MF
authors.lastname: Reschke
authors.forename: D E
authors.initials: DE
authors.lastname: Parker
authors.forename: D L
authors.initials: DL
authors.lastname: Harm
authors.forename: L
authors.initials: L
authors.lastname: Michaud
mesh_terms: D000222:Adaptation, Physiological; D006801:Humans; D009039:Motion Perception; D009041:Motion Sickness / Q000517:prevention & control*; D010812:Physical Stimulation; D013026:Space Flight / Q000295:instrumentation; D014893:Weightlessness