A new device for measuring motor control ability by a visual stimulus ?Toward the analysis of clumsiness for eye-hand coordination task corresponding to a visual target?

学習障害児や注意欠陥多動性障害児などの軽度発達障害児はそれぞれの主症状とともに、巧緻動作の未熟さなど不器用さが主訴としてあげられることが多く、姿勢調節や目と手の協応性の問題などの影響が指摘されている。今回、視覚刺激に誘導された運動制御を測定する機器の開発を行った。測定課題は水平方向へ移動する光点に合わせて左右のつまみ力を調整するものであり光点の動きとの時間的なずれと力の調節の相違を分析した。その結果、運動開始のタイミングは片手に比べ両手で行ったときに向上することが明らかになり、つまみ力の調整でも片手での試行に比べ両手での試行がより光点の動きに合わせることが可能であることが明らかになった。今回の視覚刺激?運動協応課題の結果が目と手の協応性を評価する机上検査に影響を与える可能性が示唆された。さらに、固有受容覚や触覚からの情報と視覚的情報の関与の度合いがタイミングや力の調節能に影響を与える可能性が示唆された。Awkward motor activities in children having mild developmental disorders may be related to a variety of factors. We developed an instrument for assessing disturbances of eye-hand coordination which may lead to awkward motor activities. The instrument consisted of a visual stimulation program where the subject tracks a light spot on a monitor with the use of a pinch-meter. The subject had to adjust their pinch forces in order to track the light spot as a visual target. Three experimental procedures were carried out using the right hand, the left hand, and finally both hands in all right-handed subjects. These experimental procedures analyzed two variables, one being the time lag between the moving target and the time of change in the pinch-force. The results showed that the time lag was reduced in the case of the right hand, the left hand, and then using both hands. Results showed that coordination of pinch-force with both hands were superior to the one hand alone. Some subjects who received a low score in the traditional motor accuracy test also had a rather large time lag. Our results suggested that the functional difference of eye-hand coordination between the right and the left hands might be influenced by visio-motor central ability. Furthermore, our results seem to indicate that the information of proprioceptional and tactile sensation may be improved in the areas of timing and the processing of visual stimulation