Coats A C, Norfleet W T
Baylor College of Medicine, Houston, Texas 77030, USA.
J Vestib Res. 1998 Mar-Apr;8(2):135-49.
We evaluated a new model of motion sickness--an enclosure decorated with visual cues to upright which was immersed either inverted or "front"-wall down, in Johnson Space Center's Weightless Environment Training Facility (WETF) pool. This "WETF False Vertical Room" (WFVR) was tested with 19 male and 3 female SCUBA diver subjects, aged 23 to 57, who alternately set clocks mounted near the room's 8 corners and made exaggerated pitch head movements. We found that (1) the WFVR test runs produced motion sickness symptoms in 56% and 36% of subjects in the room-inverted and room-front-down positions, respectively. (2) Pitch head movements were the most provocative acts, followed closely by setting the clocks--particularly when a clock face filled the visual field. (3) When measured with a self-ranking questionnaire, terrestrial motion sickness susceptibility correlated strongly (P < 0.005) with WFVR sickness susceptibility. (4) Standing instability, measured with a modified Fregly-Graybiel floor battery, also correlated strongly (P < 0.005) with WFVR sickness susceptibility. This result may reflect a relationship between visual dominance and WFVR sickness. (5) A control study demonstrated that the inverted and front-down positions produced WFVR sickness, but the upright position did not, and that adaptation may have occurred in some subjects with repeated exposure. The WFVR could become a useful terrestrial model of space motion sickness (SMS) because it duplicates the nature of the gravity-dependent sensory conflicts created by microgravity (visual and otolith inputs conflict while somatosensory gravity cues are minimized), and it also duplicates the nature of the provocative stimulus (sensory environment "rule change" versus application of motion to passive subject) more closely than any other proposed terrestrial SMS model. Also, unlike any other proposed terrestrial SMS model, the WFVR incorporates whole-body movement in all three spatial dimensions. However, the WFVR's sensory environment differs from that created by spaceflight in several respects, including the presence of frictional drag on limb movement, magnification at the face-mask-water interface, greater otolith conflict, exhaled bubbles, and the presence of some gravity-dependent somatosensory inputs.
我们在约翰逊航天中心的失重环境训练设施（WETF）水池中评估了一种新的晕动病模型——一个装饰有垂直视觉线索的舱室，该舱室可以倒置或“前壁”向下浸入水中。这个“WETF假垂直室”（WFVR）对19名年龄在23至57岁之间的男性和3名女性潜水员受试者进行了测试，他们轮流设置安装在房间八个角落附近的时钟，并进行夸张的俯仰头部运动。我们发现：（1）在WFVR测试中，分别有56%和36%的受试者在舱室倒置和舱室前壁向下的位置出现了晕动病症状。（2）俯仰头部运动是最具刺激性的行为，其次是设置时钟——特别是当时钟盘面填满视野时。（3）通过自我评分问卷测量，地面晕动病易感性与WFVR晕动病易感性密切相关（P < 0.005）。（4）用改良的弗雷格利 - 格雷比尔地板电池测量的站立不稳定性也与WFVR晕动病易感性密切相关（P < 0.005）。这一结果可能反映了视觉主导与WFVR晕动病之间的关系。（5）一项对照研究表明，倒置和前壁向下的位置会导致WFVR晕动病，但直立位置不会，并且一些受试者在反复暴露后可能会出现适应。WFVR可能会成为一种有用的地面太空晕动病（SMS）模型，因为它复制了微重力产生的与重力相关的感觉冲突的本质（视觉和耳石输入相互冲突，而体感重力线索最小化），并且它也比任何其他提出的地面SMS模型更紧密地复制了刺激性刺激的本质（感觉环境“规则变化”与对被动受试者施加运动）。此外，与任何其他提出的地面SMS模型不同，WFVR在所有三个空间维度上都纳入了全身运动。然而，WFVR的感觉环境在几个方面与太空飞行所创造的环境不同，包括肢体运动时存在摩擦阻力、面罩 - 水界面处的放大作用、更大的耳石冲突、呼出的气泡以及一些与重力相关的体感输入的存在。
