|Budget Amount *help
¥7,100,000 (Direct Cost : ¥7,100,000)
Fiscal Year 1997 : ¥3,100,000 (Direct Cost : ¥3,100,000)
Fiscal Year 1996 : ¥4,000,000 (Direct Cost : ¥4,000,000)
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.