Braun J, Julesz B
California Institute of Technology, Division of Biology, Pasadena 91125, USA.
Percept Psychophys. 1998 Jan;60(1):1-23. doi: 10.3758/bf03211915.
We used a concurrent-task paradigm to investigate the attentional cost of simple visual tasks. As in earlier studies, we found that detecting a unique orientation in an array of oriented elements ("pop-out") carries little or no attentional cost. Surprisingly, this is true at all levels of performance and holds even when pop-out is barely discriminable. We discuss this finding in the context of our previous report that the attentional cost of stimulus detection is strongly influenced by the presence and nature of other stimuli in the display (Braun, 1994b). For discrimination tasks, we obtained a similarly mixed outcome: Discrimination of letter shape carried a high attentional cost whereas discrimination of color and orientation did not. Taken together, these findings lead us to modify our earlier position on the attentional costs of detection and discrimination tasks (Sagi & Julesz, 1985). We now believe that observers enjoy a significant degree of "ambient" visual awareness outside the focus of attention, permitting them to both detect and discriminate certain visual information. We hypothesize that the information in question is selected by a competition for saliency at the level of early vision.
我们采用并发任务范式来研究简单视觉任务的注意力成本。与早期研究一样，我们发现，在一组有方向的元素阵列中检测独特方向（“弹出”）几乎不会产生注意力成本。令人惊讶的是，在所有表现水平下都是如此，即使“弹出”几乎无法辨别时也是如此。我们结合之前的报告来讨论这一发现，之前的报告指出，刺激检测的注意力成本受到显示屏中其他刺激的存在和性质的强烈影响（布劳恩，1994b）。对于辨别任务，我们也得到了类似的混合结果：字母形状的辨别具有较高的注意力成本，而颜色和方向的辨别则没有。综合这些发现，我们修改了我们早期关于检测和辨别任务注意力成本的观点（萨吉和朱尔兹，1985）。我们现在认为，观察者在注意力焦点之外享有显著程度的“周边区域”视觉意识，可以让他们检测和辨别某些视觉信息。我们假设，所讨论的信息是通过早期视觉层面的显著性竞争来选择的。
