Zhaoping Li
Department of Computer Science, University College London, London WC1E 6BT, UK.
Vision (Basel). 2018 Feb 24;2(1):12. doi: 10.3390/vision2010012.
An eye-of-origin singleton, e.g., a bar shown to the left eye among many other bars shown to the right eye, can capture attention and gaze exogenously or reflexively, even when it appears identical to other visual input items in the scene and when the eye-of-origin feature is irrelevant to the observer's task. Defining saliency as the strength of exogenous attraction to attention, we say that this eye-of-origin singleton, or its visual location, is salient. Defining the ocularity of a visual input item as the relative difference between its left-eye input and its right-eye input, this paper shows the general case that an ocularity singleton is also salient. For example, a binocular input item among monocular input items is salient, so is a left-eye-dominant input item (e.g., a bar with a higher input contrast to the left eye than to the right eye) among right-eye-dominant items. Saliency by unique input ocularity is analogous to saliency by unique input colour (e.g., a red item among green ones), as colour is determined by the relative difference(s) between visual inputs to different photoreceptor cones. Just as a smaller colour difference between a colour singleton and background items makes this singleton less salient, so does a smaller ocularity difference between an ocularity singleton and background items. While a salient colour difference is highly visible, a salient ocularity difference is often perceptually invisible in some cases and discouraging gaze shifts towards it in other cases, making its behavioural manifestation not as apparent. Saliency by ocularity contrast provides another support to the idea that the primary visual cortex creates a bottom-up saliency map to guide attention exogenously.
一个源于特定眼睛的单独元素，例如在向右眼展示的许多其他条状物中向左眼展示的一条，即使它与场景中的其他视觉输入项看起来相同，并且当源于特定眼睛的特征与观察者的任务无关时，也能外源性地或反射性地吸引注意力并引导注视。将显著性定义为对外源性注意力吸引的强度，我们说这个源于特定眼睛的单独元素或其视觉位置是显著的。将视觉输入项的视性定义为其左眼输入和右眼输入之间的相对差异，本文表明一般情况下视性单独元素也是显著的。例如，单眼输入项中的双眼输入项是显著的，右眼主导项中的左眼主导输入项（例如，与右眼相比，左眼输入对比度更高的条状物）也是显著的。通过独特输入视性产生的显著性类似于通过独特输入颜色产生的显著性（例如，绿色物品中的红色物品），因为颜色是由不同光感受器锥体的视觉输入之间的相对差异决定的。就像颜色单独元素与背景项之间较小的颜色差异会使这个单独元素不那么显著一样，视性单独元素与背景项之间较小的视性差异也是如此。虽然显著的颜色差异很容易被看到，但在某些情况下，显著的视性差异在感知上往往是不可见的，而在其他情况下则会阻碍注视转向它，使其行为表现不那么明显。视性对比度产生的显著性为初级视觉皮层创建自下而上的显著性图以外源性地引导注意力这一观点提供了另一个支持。
