Résumé
Motion sickness is a physiological disorder induced by abnormal acceleration stimuli during spaceflight, aviation or sailing. It has been confirmed that the vestibular system, as the core for locomotion sensing and acceleration information processing, plays key roles in motion sickness initiation and autonomic symptom development. Although the mechanism of motion sickness is still unclear, there have been new breakthroughs in recent years about the physiological basis of sensory conflict theory and the neural mechanism of autonomic reflex. This paper reviewed the progress in the vestibulo-visuo-proprioception information integration, the involvement of vestibulo-hippocampus and vestibulo-cortex in locomotion information processing, vestibulo-autonomic reflex pathway, vestibular neurotransmitter system and anti-motion sickness drug targets, laying a foundation for promoting the development and application of novel countermeasures for motion sickness.
Résumé
Objective: To observe the changes of motion sickness incidences under normal temperature (NT), high environmental temperature (HT), and high environmental temperature/humidity (HTHH), so as to study the influence of high environmental temperature/humidity on the onset of motion sickness. Methods: A total of 459 male students in a university,. aged 18-23 years and with normal physical condition/ability, were subjected for Coriolis acceleration test under the condition of 20°C/55%RH (NT), 38°CM/55%RH (HT), and 38°C/80%RH (HTHH); then the motion sickness severity was evaluated using Graybiel scale. Results: The motion sickness incidences of NT, HT, and HTHH groups were 47.93%, 68.94%, and 100%, and Graybiel scores were (2.07±3.12), (6.06±5.45) and (11.87±3.42), respectively, with the latter significantly higher than those of the former two for Graybiel scores (P<0.000 1). The severity scales of motion sickness were also significantly different between the three groups (P<0.000 1). Conclusion: High environmental temperature and humidity can accelerate the onset of motion sickness and aggravate the symptoms of motion sickness.
Résumé
Objective To compare the effects of location and orientation training on the improvement of visual motor coordination under up down reversed vision, provide reference for the preventation of space motion sickness and the design of adaptation training for sensory conflict. Method Sixteen subjects were instructed to complete the maze task wearing the up down reversing prism spectacle before and after the location training and the orientation training. Both trainings lasted 30 minutes respectively. The error rate and the executing time during the maze test were analyzed and compared. Results Both trainings significantly decreased the error rate and the executing time. In addition, the results of different training methods had significant difference, and the effects of the orientation training was better than that of the location training under up-down reversed vision. Conclusions Under the sensory conflict environment arising from the visual change, the adaptation induced by some task training could also be of benefit to some other task training so as to improve the ability of visual-motor coordination and the adaption to the sensory conflict. However, different trainings could have various degrees of improvement.