Kramer P D, Roberts D C, Shelhamer M, Zee D S
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
J Vestib Res. 1998 Sep-Oct;8(5):363-79.
Testing of the vestibular system requires a vestibular stimulus (motion) and/or a visual stimulus. We have developed a versatile, low cost, stereoscopic visual display system, using "virtual reality" (VR) technology. The display system can produce images for each eye that correspond to targets at any virtual distance relative to the subject, and so require the appropriate ocular vergence. We elicited smooth pursuit, "stare" optokinetic nystagmus (OKN) and after-nystagmus (OKAN), vergence for targets at various distances, and short-term adaptation of the vestibulo-ocular reflex (VOR), using both conventional methods and the stereoscopic display. Pursuit, OKN, and OKAN were comparable with both methods. When used with a vestibular stimulus, VR induced appropriate adaptive changes of the phase and gain of the angular VOR. In addition, using the VR display system and a human linear acceleration sled, we adapted the phase of the linear VOR. The VR-based stimulus system not only offers an alternative to more cumbersome means of stimulating the visual system in vestibular experiments, it also can produce visual stimuli that would otherwise be impractical or impossible. Our techniques provide images without the latencies encountered in most VR systems. Its inherent versatility allows it to be useful in several different types of experiments, and because it is software driven it can be quickly adapted to provide a new stimulus. These two factors allow VR to provide considerable savings in time and money, as well as flexibility in developing experimental paradigms.
前庭系统测试需要前庭刺激（运动）和/或视觉刺激。我们利用“虚拟现实”（VR）技术开发了一种多功能、低成本的立体视觉显示系统。该显示系统可以为每只眼睛生成与相对于受试者的任何虚拟距离处的目标相对应的图像，因此需要适当的眼辐辏。我们使用传统方法和立体显示来诱发平稳跟踪、“凝视”视动性眼震（OKN）和后眼震（OKAN）、不同距离目标的辐辏以及前庭眼反射（VOR）的短期适应性变化。两种方法下的跟踪、OKN和OKAN情况相当。当与前庭刺激一起使用时，VR会引起角VOR的相位和增益的适当适应性变化。此外，使用VR显示系统和人体线性加速度雪橇，我们调整了线性VOR的相位。基于VR的刺激系统不仅为前庭实验中刺激视觉系统的更繁琐方法提供了一种替代方案，还可以产生否则不切实际或不可能的视觉刺激。我们的技术提供的图像没有大多数VR系统中遇到的延迟。其固有的多功能性使其可用于几种不同类型的实验，并且由于它是软件驱动的，因此可以快速调整以提供新的刺激。这两个因素使VR能够在时间和金钱上节省大量成本，同时在开发实验范式方面具有灵活性。
