University of Groningen, Groningen, The Netherlands.
Hum Mov Sci. 2012 Jun;31(3):487-501. doi: 10.1016/j.humov.2011.07.014. Epub 2011 Nov 29.
Although variations in the standard prehensile pattern can be found in the literature, these alternative patterns have never been studied systematically. This was the goal of the current paper. Ten participants picked up objects with a pincer grip. Objects (3, 5, or 7cm in diameter) were placed at 30, 60, 90, or 120cm from the hands' starting location. Usually the hand was opened gradually to a maximum immediately followed by hand closing, called the standard hand opening pattern. In the alternative opening patterns the hand opening was bumpy, or the hand aperture stayed at a plateau before closing started. Two participants in particular delayed the start of grasping with respect to start of reaching, with the delay time increasing with object distance. For larger object distances and smaller object sizes, the bumpy and plateau hand opening patterns were used more often. We tentatively concluded that the alternative hand opening patterns extended the hand opening phase, to arrive at the appropriate hand aperture at the appropriate time to close the hand for grasping the object. Variations in hand opening patterns deserve attention because this might lead to new insights into the coordination of reaching and grasping.
尽管文献中可以发现标准握持模式的变化，但这些替代模式从未被系统研究过。这就是本文的目的。十位参与者用钳子夹的方式捡起物品。物品（直径 3、5 或 7 厘米）放置在距手起始位置 30、60、90 或 120 厘米处。通常手会逐渐张开到最大，然后立即开始合拢，这称为标准手张开模式。在替代的张开模式中，手的张开是颠簸的，或者在手开始合拢之前，手的孔径保持在一个平台上。特别是有两个参与者相对于伸手开始延迟了抓握的开始，延迟时间随着物体距离的增加而增加。对于更大的物体距离和更小的物体尺寸，使用颠簸和平台手张开模式的频率更高。我们暂时得出结论，替代的手张开模式延长了手张开的阶段，以便在适当的时间到达适当的手孔径，以便关闭手以抓取物体。手张开模式的变化值得关注，因为这可能会为伸手和抓握的协调提供新的见解。
