Palluel-Germain R, Boy F, Orliaguet J P, Coello Y
Laboratoire de Psychologie et NeuroCognition (LPNC), CNRS UMR 5105, Université Pierre Mendès France, Grenoble II, 1251, Avenue Centrale -- BP 47, 38040 Grenoble Cedex 9, France.
Neurosci Lett. 2006 Jun 19;401(1-2):97-102. doi: 10.1016/j.neulet.2006.02.072. Epub 2006 Mar 23.
The main objective of the present study is to show that the visual context can influence the trajectory formation of grasping movements. We asked participants to reach and grasp a cylinder disposed at three different positions: -20 degrees , 0 degrees and 20 degrees of eccentricity with respect to the midsagittal axis. Grasping movements were performed in a direct and in an indirect visual feedback condition (i.e., controlled through a vertical video display). Results revealed that for grasping movements directed toward objects located at -20 degrees and 0 degrees , path curvatures of the wrist, the thumb and the index finger were significantly straighter in the indirect visual feedback condition. However, no significant difference concerning hand path curvature was observed when the movement was directed toward the object located at 20 degrees . This suggests that grasping movements controlled through a remote visual feedback tend to be planned in extrinsic space and that the effect of the visual context on movement planning appears to be not isotropic over the workspace.
本研究的主要目的是表明视觉环境会影响抓握动作的轨迹形成。我们要求参与者伸手去抓一个放置在相对于正中矢状轴三个不同位置的圆柱体：-20度、0度和20度的偏心率处。抓握动作在直接和间接视觉反馈条件下进行（即通过垂直视频显示器控制）。结果显示，对于指向位于-20度和0度物体的抓握动作，在间接视觉反馈条件下，手腕、拇指和食指的路径曲率明显更直。然而，当动作指向位于20度的物体时，未观察到手部路径曲率有显著差异。这表明通过远程视觉反馈控制的抓握动作倾向于在外在空间中进行规划，并且视觉环境对运动规划的影响在工作空间中似乎不是各向同性的。
