Jordan K, Pataky T C, Newell K M
Department of Kinesiology, 266 Recreation Building, The Pennsylvania State University, University Park, PA 16802, USA.
J Mot Behav. 2005 Jul;37(4):285-94. doi: 10.3200/JMBR.37.4.285-294.
The authors investigated the structure of force production and variability as a function of grip configuration and width during precision grasping. Variability was studied in absolute (standard deviation) and relative (coefficient of variation) terms; in addition, the authors used approximate entropy to examine regularity. In Experiment 1, the participants (N = 14) used a 2-digit grasp (thumb, index), whereas in Experiment 2, the participants (N = 11) used a 3-digit grasp (thumb, index, middle). The level and regularity of force increased with grip width. The amount of variability was least at narrow grip widths for 2-digit grasping and greatest at narrow grip widths for 3-digit grasping. That pattern of findings is not necessitated by the mechanical equilibrium of grasping; thus, it also reflected adaptive neural reorganization of force output to task demands.
作者研究了在精确抓握过程中，力产生的结构和变异性作为握姿配置和宽度的函数关系。变异性从绝对（标准差）和相对（变异系数）两个方面进行研究；此外，作者还使用近似熵来检验规律性。在实验1中，参与者（N = 14）采用双指抓握（拇指、食指），而在实验2中，参与者（N = 11）采用三指抓握（拇指、食指、中指）。力的水平和规律性随着握宽增加。对于双指抓握，在窄握宽时变异性最小；对于三指抓握，在窄握宽时变异性最大。这种发现模式并非由抓握的机械平衡所决定；因此，它也反映了力输出对任务需求的适应性神经重组。
