Quantifying feedforward control: a linear scaling model for fingertip forces and object weight.
Quantifying feedforward control: a linear scaling model for fingertip forces and object weight.
复制标题
量化前馈控制：指尖力和物体重量的线性缩放模型。
DOI：
10.1152/jn.00065.2015
复制
发表时间：
2015
影响因子：
2.5
通讯作者：
Raghavan,Preeti
中科院分区：
文献类型：
--
作者：
Lu,Ying;Bilaloglu,Seda;Aluru,Viswanath;Raghavan,Preeti
在物体被举起之前根据物体属性预测最佳指尖力的能力被称为前馈控制，并且它被认为是由于物体属性的内部表示的形成而发生的。通过使用配备力传感器的定制抓握装置，人们广泛研究了指尖对不同重量物体的力的控制。前馈控制是通过在物体被提升之前垂直（负载）力的变化率来测量的。然而，载荷力和物体重量的变化率之间的精确关系以及它在人群中健康个体之间的变化方式还不清楚。使用10个不同的重量，我们已经表明，有一个对数线性关系之间的指尖负荷力率和神经系统完整的个人之间的重量。我们发现，在一次练习举重后，随着体重的增加，峰值负荷力率（PLFR）以固定的百分比增加，这种比例在健康受试者中很常见。然而，在任何给定的重量下，PLFR的水平在个体之间是不同的，并且与举起物体所涉及的肌肉的效率有关，在这种情况下是手腕和手指伸肌。这些结果量化前馈控制过程中的把握和升降机之间的健康个体，并提供了新的基准来解释数据神经功能受损的人群，以及一种手段来评估的影响，恢复前馈控制和肌肉控制的关系的干预措施。
The ability to predict the optimal fingertip forces according to object properties before the object is lifted is known as feedforward control, and it is thought to occur due to the formation of internal representations of the object's properties. The control of fingertip forces to objects of different weights has been studied extensively by using a custom-made grip device instrumented with force sensors. Feedforward control is measured by the rate of change of the vertical (load) force before the object is lifted. However, the precise relationship between the rate of change of load force and object weight and how it varies across healthy individuals in a population is not clearly understood. Using sets of 10 different weights, we have shown that there is a log-linear relationship between the fingertip load force rates and weight among neurologically intact individuals. We found that after one practice lift, as the weight increased, the peak load force rate (PLFR) increased by a fixed percentage, and this proportionality was common among the healthy subjects. However, at any given weight, the level of PLFR varied across individuals and was related to the efficiency of the muscles involved in lifting the object, in this case the wrist and finger extensor muscles. These results quantify feedforward control during grasp and lift among healthy individuals and provide new benchmarks to interpret data from neurologically impaired populations as well as a means to assess the effect of interventions on restoration of feedforward control and its relationship to muscular control.