Furuya S, Kinoshita H
Graduate School of Medicine, Osaka University, Health and Sports Science Building, 1-17 Machikaneyama-chou, Toyonaka, Osaka 560-0043, Japan.
Neuroscience. 2008 Oct 2;156(2):390-402. doi: 10.1016/j.neuroscience.2008.07.028. Epub 2008 Jul 25.
The problem of skill-level-dependent modulation in the joint dynamics of multi-joint arm movements is addressed in this study using piano keystroke performed by expert and novice piano players. Using the measured kinematic and key-force data, the time varying net, gravitational, motion-dependent interaction (INT), key-reaction (REA), and muscular (MUS) torques at the shoulder, elbow, wrist, and metacarpophalangeal (MP) joints were computed using inverse dynamics techniques. INTs generated at the elbow and wrist joints, but not those at the MP joint, were greater for the experts as compared with the novices. REA at the MP joint, but not at the other joints, was less for the experts as compared with the novices. The MUSs at the MP, wrist, and elbow joints were smaller, and that at the shoulder joint was larger for the experts as compared with the novices. The experts also had a lesser inter-strike variability of key striking force and key descending velocity as compared with the novices. These findings indicated that the relationship among the INT, REA, and MUS occurring at the joints of the upper-extremity differed between the expert and novice piano players, suggesting that the organization of multi-joint arm movement is modulated by long-term motor training toward facilitating both physiological efficiency and movement accuracy.
本研究利用专业和新手钢琴演奏者的钢琴按键动作，探讨了多关节手臂运动关节动力学中与技能水平相关的调制问题。利用测量得到的运动学和按键力数据，采用逆动力学技术计算了肩部、肘部、腕部和掌指关节处随时间变化的净扭矩、重力扭矩、运动相关相互作用（INT）扭矩、按键反应（REA）扭矩和肌肉（MUS）扭矩。与新手相比，专家在肘部和腕部关节产生的INT更大，但在掌指关节处并非如此。与新手相比，专家在掌指关节而非其他关节处的REA更小。与新手相比，专家在掌指关节、腕部和肘部关节处的MUS更小，而在肩部关节处更大。与新手相比，专家按键敲击力和按键下降速度的击打间变异性也更小。这些发现表明，专业和新手钢琴演奏者上肢关节处的INT、REA和MUS之间的关系有所不同，这表明多关节手臂运动的组织通过长期的运动训练得到调制，以提高生理效率和运动准确性。
