Duncan J
MRC Applied Psychology Unit, Cambridge, UK.
Perception. 1989;18(4):457-69. doi: 10.1068/p180457.
A new theory of visual search is tested experimentally with simple colour patches. The essential element of this new theory is that, whatever the search materials, efficiency increases continuously with (i) decreasing similarity between targets and nontargets, and (ii) increasing similarity between one nontarget and another. Control of 'attention' (access to visual short-term memory) is seen as a competitive interaction between display elements, and the theory shows how stimulus similarities influence the outcome of this competition. One alternative view is that parallel visual processes are limited to local mismatch detection. Search is parallel if the target forms a break in an otherwise homogeneous field, but is serial when absolute stimulus identification is required. It is shown, however, that even colour identification can be parallel, providing targets and nontargets are sufficiently dissimilar. A second alternative view is that search for simple features is parallel whereas search for conjunctions is serial. Conjunction search, however, has a characteristic similarity structure: different kinds of nontarget each share one relevant attribute with the target, but none with one another. When this structure is mimicked in search for colour patches, correspondingly poor performance is obtained.
一种视觉搜索的新理论通过简单的色块进行了实验测试。这一新理论的核心要素是，无论搜索材料如何，效率会随着以下两点持续提高：（i）目标与非目标之间的相似度降低；（ii）一个非目标与另一个非目标之间的相似度增加。“注意力”（对视觉短期记忆的访问）的控制被视为显示元素之间的竞争性相互作用，该理论展示了刺激相似度如何影响这种竞争的结果。另一种观点认为，并行视觉过程仅限于局部不匹配检测。如果目标在其他方面均一的区域中形成一个断点，搜索就是并行的，但当需要绝对刺激识别时，搜索就是串行的。然而，研究表明，只要目标与非目标足够不同，即使是颜色识别也可以是并行的。另一种观点认为，对简单特征的搜索是并行的，而对联结特征的搜索是串行的。然而，联结搜索具有一种特征性的相似结构：不同类型的非目标各自与目标共享一个相关属性，但彼此之间没有共享。当在搜索色块时模仿这种结构时，会相应地得到较差的表现。
