European vestibular experiments on the Spacelab-1 mission: 4. Thresholds of perception of whole-body linear oscillation.
Thresholds for the detection of linear oscillatory motion at 0.3 Hz in the X, Y and Z body axes were determined during the flight of Spacelab-1 and on the ground pre- and post-flight, using the method of limits with a single staircase procedure. Pre-flight, Z axis thresholds (mean 0.077 ms-2) were significantly higher than X and Y thresholds (mean 0.029 ms-2). Measures obtained on three crew members in-flight exhibited thresholds greater, by a factor of 1.5-4.3, than those obtained pre-flight. Post-flight, two crew members had significantly elevated X and Y axis thresholds whereas the other two crew members had lowered thresholds in X, Y and Z axes. In general, thresholds had returned to pre-flight levels by the second post-flight day. A possible explanation for these somewhat disparate responses is presented.
D000054:Acceleration; D000222:Adaptation, Physiological; D006801:Humans; D007699:Kinesthesis / Q000502:physiology*; D009041:Motion Sickness / Q000209:etiology; D010037:Otolithic Membrane / Q000502:physiology; D011601:Psychophysics; D012684:Sensory Thresholds; D013026:Space Flight; D014722:Vestibule, Labyrinth / Q000502:physiology*; D014893:Weightlessness