The University of Manchester, Manchester, UK.
Brigham and Women's Hospital, Boston, MA, USA.
Cogn Res Princ Implic. 2024 Mar 19;9(1):15. doi: 10.1186/s41235-024-00543-z.
In any visual search task in the lab or in the world, observers will make errors. Those errors can be categorized as "deterministic": If you miss this target in this display once, you will definitely miss it again. Alternatively, errors can be "stochastic", occurring randomly with some probability from trial to trial. Researchers and practitioners have sought to reduce errors in visual search, but different types of errors might require different techniques for mitigation. To empirically categorize errors in a simple search task, our observers searched for the letter "T" among "L" distractors, with each display presented twice. When the letters were clearly visible (white letters on a gray background), the errors were almost completely stochastic (Exp 1). An error made on the first appearance of a display did not predict that an error would be made on the second appearance. When the visibility of the letters was manipulated (letters of different gray levels on a noisy background), the errors became a mix of stochastic and deterministic. Unsurprisingly, lower contrast targets produced more deterministic errors. (Exp 2). Using the stimuli of Exp 2, we tested whether errors could be reduced using cues that guided attention around the display but knew nothing about the content of that display (Exp3a, b). This had no effect, but cueing all item locations did succeed in reducing deterministic errors (Exp3c).
在实验室或现实世界中的任何视觉搜索任务中，观察者都会犯错。这些错误可以分为“确定性”：如果您在这次显示中错过了这个目标，那么您肯定会再次错过它。或者，错误可能是“随机的”，每次试验都会以一定的概率随机发生。研究人员和从业者一直试图减少视觉搜索中的错误，但不同类型的错误可能需要不同的技术来减轻。为了在简单的搜索任务中对错误进行经验分类，我们的观察者在“L”干扰项中搜索字母“T”，每次显示呈现两次。当字母清晰可见（白色字母在灰色背景上）时，错误几乎完全是随机的（实验 1）。在显示的第一次出现时犯的错误并不能预测在第二次出现时会犯错误。当字母的可见性被操纵（不同灰度级的字母在嘈杂的背景上）时，错误变成了随机和确定性的混合。毫不奇怪，对比度较低的目标会产生更多确定性的错误。（实验 2）。使用实验 2 的刺激，我们测试了使用提示来引导注意力围绕显示，但对显示的内容一无所知的提示是否可以减少错误（实验 3a、b）。这没有效果，但提示所有项目位置确实成功地减少了确定性错误（实验 3c）。
