運動感覚に対する視覚の優位性とその定量化

抄録

Certain studies concerning human perception has revealed that vision dominates all the other sense modalities. This study tried to confirm the visual dominance over kinesthesis by taking a case of memorizing an arm movement which was visually monitored, and to record a score in an attempt to demonstrate the degree of visual dominance over kinesthesis. An arm positioning task was selected for this experiment, and its basic procedure of measurement will follow. First, subjects memorized a standard distance by vision and kinesthesis. While moving the right arm for a certain standard distance, they were allowed to observe the movement by vision. But some artificial conflicts were produced between these two sense modalities in this case. Then, subjects attempted to repeat the arm movement for the same standard distance, when the conflicts were removed. How much the reproduced distance was close to the visual or kinesthetic information which were conflicting with each other, was recorded, which was presented in per cent scores. The results indicated the followings: 1) Almost all subjects did not realize the conflicts. While the visual dominance score showed that vision dominated kinesthesis, the score also showed that the dominance, was not complete. 2) The longer the standard distance, the stronger was the visual dominance, which may be interpreted as follows. As the standard distance increased, the kinesthetic matching errors became greater, while the visual matching errors were relatively constant. These trends suggested that when the standard distance became longer, subjects depended on the visual information more strongly than when it was shorter. 3) Individual differences of visual dominance score were examined. The results did not necessarily support the existence of indivisual differences. But, further studies may be necessary to draw any definite conclusions on this matter.