Schenk Thomas, Utz Kathrin S, Hesse Constanze
Department of Psychology, Ludwig-Maximilians University, Munich, Germany.
Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany.
Vision Res. 2017 Nov;140:140-143. doi: 10.1016/j.visres.2017.05.017. Epub 2017 Oct 7.
The violation of Weber's law in grasping has been presented as evidence for the claim that grasping is guided by visual information which is distinct from the information used in perceptual tasks. Previously, we contested this claim and argued that biomechanical constraints of the hand might explain why Weber's law cannot be reliably uncovered in grasping movements. In a recent article Manzone and colleagues (2017) show that pantomime grasping follows Weber's law even with objects whose width is close to the hand's biomechanical limit. In this commentary we explain why the biomechanical account does not necessarily predict the violation of Weber's law in a pantomime grasping task and why it seems problematic to use adherence or violation of Weber's law as a criterion to assign tasks to different anatomical pathways.
抓握过程中对韦伯定律的违背被视为一种证据，用以支持抓握是由视觉信息引导的这一观点，该视觉信息不同于感知任务中所使用的信息。此前，我们对这一观点提出质疑，并认为手部的生物力学限制或许可以解释为何在抓握动作中无法可靠地发现韦伯定律。在最近一篇文章中，曼佐内及其同事（2017年）表明，即使对于宽度接近手部生物力学极限的物体，模拟抓握也遵循韦伯定律。在这篇评论中，我们解释了为何生物力学解释不一定能预测在模拟抓握任务中对韦伯定律的违背，以及为何将是否遵循韦伯定律作为将任务分配到不同解剖学路径的标准似乎存在问题。
