Levinthal Brian R, Lleras Alejandro
Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA.
J Vis. 2008 Nov 21;8(15):12.1-15. doi: 10.1167/8.15.12.
The Distractor Previewing Effect (DPE) is an inter-trial effect that arises in efficient visual searches where participants are asked to find a feature oddball in the display. Specifically, the DPE is the finding that an observer's ability to focus on an oddball target is impaired if, on the immediately preceding trial, no target was present and all distractors shared a visual feature with the current target (e.g., all objects were red on trial N, and the target was a red oddball on trial N + 1). Though recent evidence suggests that the DPE emerges from an attentional bias against focusing on a recently examined feature common to all stimuli in a target-absent trial, it is unclear whether this inhibition is formed for all features in target-absent trials, or is instead limited to the search-relevant feature. In two experiments we manipulated task instructions while keeping displays identical, alternating which feature (shape or color) was relevant for the search task and which was not. Our results showed that attentional inhibition is applied only to the search-relevant feature. Additionally we found that although search-irrelevant features affect search times, these effects are independent of any relationship to the previous trial.
干扰项预视效应（DPE）是一种试间效应，出现在高效视觉搜索任务中，即要求参与者在显示屏中找出一个特征异常的目标。具体而言，DPE是指这样一个发现：如果在前一次试验中没有目标出现，且所有干扰项都与当前目标共享一个视觉特征（例如，在第N次试验中所有物体都是红色的，而在第N + 1次试验中目标是一个红色的异常项），那么观察者聚焦于异常目标的能力就会受损。尽管最近的证据表明，DPE源于对在前一次无目标试验中所有刺激共有的最近检查过的特征的注意力偏差，但尚不清楚这种抑制是在无目标试验中对所有特征形成的，还是仅限于与搜索相关的特征。在两个实验中，我们在保持显示屏相同的情况下操纵任务指令，交替改变哪个特征（形状或颜色）与搜索任务相关以及哪个特征不相关。我们的结果表明，注意力抑制仅应用于与搜索相关的特征。此外，我们发现，尽管与搜索无关的特征会影响搜索时间，但这些影响与前一次试验的任何关系无关。
