Dobkins Karen R, Lewis Lindsay B, Fine Ione
Department of Psychology, University of California, San Diego, La Jolla, 92093, USA.
Vision Res. 2006 Oct;46(20):3360-72. doi: 10.1016/j.visres.2006.05.017. Epub 2006 Jul 18.
Several previous studies in adults have investigated how one- and two-dimensional moving features are integrated into a coherent global motion percept by studying the "barber-pole illusion"; when a one-dimensional moving grating is presented within a rectangular aperture, the two-dimensional line terminators at the edges of the aperture bias the perceived direction of motion toward the longer axis of the aperture. In the current study, we used barber-pole stimuli to investigate the development of motion mechanisms that integrate one- and two-dimensional motion signals. Using a directional eye movement technique, we measured responses to obliquely moving gratings presented within horizontally vs. vertically oriented apertures, in infants (ages 2-5 months) and adults. For all ages, we found that horizontal eye movements were significantly stronger when gratings were presented within horizontal than within vertical apertures, as predicted by the barber-pole illusion. Additionally, we devised a way to infer the "effective shift" in eye movement direction produced by the barber-pole illusion. Using a simple motion integration model, effective shift values were then used to calculate the relative weightings of one- and two-dimensional motion signals to direction coding. The results show that by 2 months of age, infants integrate one- and two-dimensional motion signals, and that the relative weighting of one- and two-dimensional signals remains roughly constant from 2 months of age into adulthood.
此前有多项针对成年人的研究，通过研究“理发店旋转招牌错觉”来探究一维和二维运动特征是如何整合为连贯的整体运动感知的；当在矩形孔径内呈现一维移动光栅时，孔径边缘的二维线条终端会使感知到的运动方向偏向孔径的长轴方向。在本研究中，我们使用理发店旋转招牌刺激来研究整合一维和二维运动信号的运动机制的发展。我们采用定向眼动技术，测量了婴儿（2至5个月大）和成年人对水平和垂直方向孔径内倾斜移动光栅的反应。对于所有年龄段，我们发现，如理发店旋转招牌错觉所预测的那样，当光栅在水平孔径内呈现时，水平眼动明显比在垂直孔径内呈现时更强。此外，我们设计了一种方法来推断由理发店旋转招牌错觉产生的眼动方向的“有效偏移”。然后，使用一个简单的运动整合模型，利用有效偏移值来计算一维和二维运动信号对方向编码的相对权重。结果表明，到2个月大时，婴儿就能整合一维和二维运动信号，并且从2个月大到成年，一维和二维信号的相对权重大致保持不变。
