Influence of visual and vestibular interaction upon the onset of motion sickness

我们研究了视觉和前庭相互作用对晕车发病的影响。在本研究中，我们进行了两项实验，一项是研究光动力（OK）刺激时的旋转/漂浮感觉，另一项是研究直线加速时视觉目标对晕动病发病的影响。在光动性眼球震颤（OKN）测试中，许多被试有旋转感。为了研究刺激强度对周围视网膜的影响，对22名健康受试者进行了两种视觉目标的OKN测试，一种视觉目标是宽视角条纹（SOKN），另一种是多随机点（ROKN）。测试对象被要求第一次告知他们通过手开关感觉到旋转感（TR）。在慢相速度时程图上，采用人工测量的方法分析了到达光动力学适应极限的时间。SOKN与ROKN的TOT、More AL平均值无显著差异。在SOKN中，TR的平均值与total的平均值几乎相似。另一方面，ROKN的平均TR显著短于SOKN。在两种测试条件下，TR与total显著相关。在恒定加速度下的OKN中，由于慢相速度不能完全跟随目标速度，视网膜发生滑移，并随着目标速度的增加而增大。视网膜滑移的增加可能通过视觉和前庭的相互作用引起光动力性眩晕。在SOKN中，我们的结果显示，TR的平均值与total的平均值相似，并且TR与total高度相关，这表明在total之前或之后不久，视网膜滑动迅速增加。另一方面，在ROKN中，虽然TR与total高度相关，但平均TR比SOKN短约14个see。ROKN对周围视野的刺激强于SOKN，视网膜滑动越少，光动力刺激引起的视致眩晕越强。此外，被试在线性加速和光动力刺激下的旋转感觉比旋转运动和光动力刺激下的旋转感觉更强烈。结果表明，刺激耳石对前庭眼相互作用和前庭自主反射的影响比对半规管的影响更大。我们的结果似乎为研究视力对晕车的影响提供了有用的信息。少

We investigated the influence between visual and vestibular interaction upon the onset of motion sickness. In this rescarch, we performed two trials, one was the investigation of rotary/floating sensation during optokinetic (OK) stimulation, and the other, that of the influence of visual target during lincar acceleration upon the onset of motion sickness.During optokinetic nystagmus (OKN) testing many test subjects feel rotary sensation. In order to investigate the influence of the stimulating strength to the peripheral retina, two kinds of OKN,one visual target of which was wide visual angle stripes (SOKN), and the other, numerous random dots (ROKN), were tested to 22 healthy subjects. The test subjects were requested to inform the first time when they felt rotatory sensation (TR) by a hand switch. The time until an optokinetic adapatation limit (TOAL) was analyzed by manual measurement on the graph of slow phase velocity time course. There was no difference between the average of TOT … More AL in SOKN and that in ROKN.In SOKN, the average of TR was almost similar to that of TOAL.On the other hand, the average of TR in ROKN was significantly shorter than that in SOKN.In both testing consitions, TR significantly correlated to TOAL.In OKN by a constant acceleration, because the slow phase velocity cannot completely follow the target velocity, retinal slip occurs and increases according to an increase of the target velocity. The increase of the retinal slip might cause optokinetic induced vertigo by the visual and vestibular interaction. In SOKN,our results, that the average of TR was similar to that of TOAL and that TR highly correlated to TOAL,indicate that the retinal slip quickly increases shortly before or after TOAL.On the other hand, in ROKN,although TR highly correlated to TOAL,the average TR was about 14 see shorter than in SOKN.In ROKN,which stimulates the periphcral visual field stronger than in SOKN, the less retinal slip could cause the stronger visual induced vertigo by optokinetic stimulation. Morcover, test subjects complained stronger rotary sensation by the summation of linear acceleration and optokinetic stimulation than by that of rotary movement and optokinetic atimulation. This results indicates that stimulation to the otolithy more strongly affected to the vestibulo-ocular intcraction and to the vestibulo autonomic reflex than to the semicircular canals.Our result seemed to provide useful information to the study about the influence of vision to motion sickness. Less