Lankheet M J, Verstraten F A
Center for Visual Science, University of Rochester, NY 14627, USA.
Vision Res. 1995 May;35(10):1401-12. doi: 10.1016/0042-6989(95)98720-t.
We have studied the effects of voluntary attention on the induction of motion aftereffects (MAEs). While adapting, observers paid attention to one of two transparently displayed random dot patterns, moving concurrently in opposite directions. Selective attention was found to modulate the susceptibility to motion adaptation very substantially. To measure the strength of the induced MAEs we modulated the signal-to-noise ratio of a real motion signal in a random dot pattern that was used to balance the aftereffect. Results obtained for adapting to single motion vectors show that the MAE can be represented as a shift of the psychometric function for motion direction discrimination. Selective attention to the different components of transparent motion altered the susceptibility to adaptation. Shifting attention from one component to the other caused a large shift of the psychometric curves, about 70-75% of the shift measured for the separate components of the transparent adapting stimulus. We conclude that attention can differentiate between spatially superimposed motion vectors and that attention modulates the activity of motion mechanisms before or at the level where adaptation gives rise to MAEs. The results are discussed in light of the role of attention in visual perception and the physiological site for attentional modulation of MAEs.
我们研究了随意注意对运动后效（MAEs）诱导的影响。在适应过程中，观察者注意两个同时以相反方向移动的透明显示随机点图案中的一个。结果发现，选择性注意对运动适应的敏感性有非常显著的调节作用。为了测量诱导MAEs的强度，我们在用于平衡后效的随机点图案中调制真实运动信号的信噪比。适应单个运动矢量所获得的结果表明，MAE可以表示为运动方向辨别心理测量函数的偏移。对透明运动不同成分的选择性注意改变了适应的敏感性。将注意力从一个成分转移到另一个成分会导致心理测量曲线发生很大偏移，约为透明适应刺激各单独成分测量偏移的70 - 75%。我们得出结论，注意能够区分空间上叠加的运动矢量，并且注意在适应产生MAEs之前或该水平上调节运动机制的活动。根据注意在视觉感知中的作用以及MAEs注意调制的生理部位对结果进行了讨论。
