Altering the visuomotor gain - Evidence that motor plans deal with vector quantities
Altering the visuomotor gain - Evidence that motor plans deal with vector quantities
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DOI：
10.1007/s00221-002-1211-9
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发表时间：
2002-12-01
影响因子：
2
通讯作者：
Viviani, P
中科院分区：
文献类型：
--
作者：
Vindras, P;Viviani, P
两个实验研究的影响，提供nonveridical知识的结果（KR）在visuomanual任务中，参与者指向简要（200毫秒）提出的目标，而看不到他们的手。通过在每次试验后显示运动终点相对于其真实位置径向移位，我们能够逐渐改变视觉手回路的增益。在实验1中，KR只提供了横向运动和一个目标的距离，但效果推广到所有方向和所有的距离。而且，它也概括到另一方面，从来没有偏见。在实验2中，nonveridical KR提供的运动沿着两个主要的对角线，需要截然不同的肌肉协同作用。向其他方向和另一方面的转移同样巨大。有人认为，结果支持的矢量编码假设，它认为，电机执行阶段的输入提供独立指定的幅度和方向的矢量从初始到最终的位置在一个外在的参考系。我们还讨论了可能的大脑结构参与偏置行动的KR。
Two experiments investigated the effects of providing nonveridical knowledge of the results (KR) in a visuomanual task in which participants pointed to briefly (200 ms) presented targets without seeing their hand. By showing after each trial the movement endpoint displaced radially with respect to its true position, we were able to alter progressively the gain of the visuomanual loop. In experiment 1, the KR was provided only for transversal movements and for one target distance, but the effect generalized to all directions and all distances. Moreover, it also generalized to the other hand that had never been biased. In experiment 2, nonveridical KR was supplied for movements along the two major diagonals which require sharply different muscle synergies. The transfer to other directions and to the other hand was equally substantial. It is argued that the results support the vector coding hypothesis, which holds that the input to the motor execution stage is supplied by specifying independently the amplitude and the direction of the vector from the initial to the final position in an extrinsic frame of reference. We also discuss the possible brain structures involved in the biasing action of the KR.