Cooperative human visuo-motor behavior under the micro-gravity

在地球上，1重力条件允许运动平衡，因此眼睛和身体运动包括头部运动以协调的方式一起工作。其中一个对运动协调不可或缺的运动被称为眼前反射（VOR）。在复杂的人体运动中，身体各肌肉之间的运动协调使视觉感知的世界相当稳定。与身体的其他肌肉运动相比，眼球运动相对来说是精细、快速和微小的。当眼睛追逐运动目标时，物理上固定的目标被认为是移动的，而运动的目标被认为是固定的。这是由眼外肌本身引起的错觉运动知觉的一个很好的例子。在大多数情况下，只有目标速度被眼球运动所改变。然而，在某些情况下，目标运动路径也会发生改变。人体在零重力下具有三维自由，这可能会比在地球上产生更多的虚幻视觉感受。对太空晕动病的频率和强度的研究已经评估了不寻常的、诱导的重力情况，如旋转、线性加速和平行摆动。视觉诱导的运动感觉或扭曲知觉已经被许多研究者评估了视觉稳定性。在我们日常生活中，在地球正常重力条件下，视觉、前庭和体感知觉是顺利协调的。人类在地面上如何在姿势改变的情况下获得视觉稳定性已经被研究过。视觉稳定性可分为静态和动态两类。静态视觉稳定性与方向有关，动态稳定性与运动感知有关。视觉稳定性受到许多其他感觉的影响，如体感、前庭和肌肉紧张。我将主要关注在微重力下眼球运动对视觉感知的前庭输入的改变。

On earth, 1-gravity condition allows for locomotor balance whereby eye and body motion including head movements works together in a coordinated manner. One such movement indispensable to locomotor coordination is referred to as the vstibular-ocular-reflex (VOR). Motion coordination among each body muscle makes the visually perceived world quite stable during complex human body movement. Eye movement is relatively fine, fast, and small in motion compared to other muscle movements of the body. When the eye pursues amoving target, the physically fixed target is perceived as if it moved, and the moving target is perceived as a fixed one. This is a good example of illusory motion perception caused by the extra ocular muscle itself. In most cases, only the target velocity is modified by eye movement. However the target motion pathway is also modified in some cases. The human body has the three dimensions of freedom under zero gravity which may cause more illusory visual perception than on the earth. Studies on the frequency and intensity of space motion sickness have evaluated the unusual, induced gravity situations such as rotation, linear acceleration, and parallel swinging. Visually induced motion sensation or distorted perception has been evaluated with respect to visual stability by many investigators. Visual, vestibular and somatosensory perception is smoothly coordinated under normal gravitational conditions of the earth in our daily lives. How humans obtain visual stability even with postural changes on the ground has been investigated. Visual stability can be categorized as static or dynamic. Static visual stability is concerned with orientation, and dynamic stability is concerned with motion perception. Visual stability is modified by many other sensations, such as somatosensory, vestibular, and muscle tension. I will mainly focus on modifications by vestibular inputs to visual perception produced by eye movement in microgravity.