Local and global representations of velocity: transparency, opponency, and global direction perception
Local and global representations of velocity: transparency, opponency, and global direction perception
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速度的局部和全局表征：透明度、对立性和全局方向感知
DOI：
10.1068/p260995
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发表时间：
1997-01-01
期刊：
影响因子：
1.7
通讯作者：
Braddick, O
中科院分区：
文献类型：
--
作者：
Braddick, O
人类受试者可以感知全局运动或包含不同局部运动的显示器中的运动，这意味着速度在多个尺度上的表示。灵活的全局方向判断现象，特别是运动透明度的现象，也提出了在任何一个尺度上的速度表示是单值还是多值的问题。一种新的基于性能的透明度测量证实了视觉系统代表了透明显示器的每个组件的方向信息。然而，钱等人提出的局部配对随机点显示的结果表明，在运动分析的最精细空间尺度上，多种速度的表示并不共存。在功能上不同的运动处理尺度可以与：(I)表现出强赢家通吃交互的局部运动检测器；(Ii)局部信号的空间积分以消除速度歧义；(Iii)如在Nowlan和Sejnowski的模型中建议的那样选择可靠的速度信号；(Iv)不一定组织在固定空间矩阵中的基于对象或基于表面的表示。这些可能性被讨论与视觉运动通路的神经生物学组织有关。
Human subjects can perceive global motion or motions in displays containing diverse local motions, implying representation of velocity at multiple scales. The phenomena of flexible global direction judgments, and especially of motion transparency, also raise the issue of whether the representation of velocity at any one scale is single-valued or multi-valued. A new performance-based measure of transparency confirms that the visual system represents directional information for each component of a transparent display. However, results with the locally paired random-dot display introduced by Qian et al, show that representations of multiple velocities do not coexist at the finest spatial scale of motion analysis. Functionally distinct scales of motion processing may be associated with (i) local motion detectors which show a strong winner-take-all interaction; (ii) spatial integration of local signals to disambiguate velocity; (iii) selection of reliable velocity signals as proposed in the model of Nowlan and Sejnowski; (iv) object-based or surface-based representations that are not necessarily organised in a fixed spatial matrix. These possibilities are discussed in relation to the neurobiological organisation of the visual motion pathway.