Tseng Chia-Huei, Jingling Li
Department of Psychology, The University of Hong Kong, Hong Kong.
Graduate Institute of Neural and Cognitive Sciences, China Medical University, Taichung, Taiwan.
PLoS One. 2015 Apr 24;10(4):e0124190. doi: 10.1371/journal.pone.0124190. eCollection 2015.
Salient distractors draw our attention spontaneously, even when we intentionally want to ignore them. When this occurs, the real targets close to or overlapping with the distractors benefit from attention capture and thus are detected and discriminated more quickly. However, a puzzling opposite effect was observed in a search display with a column of vertical collinear bars presented as a task-irrelevant distractor [6]. In this case, it was harder to discriminate the targets overlapping with the salient distractor. Here we examined whether this effect originated from factors known to modulate attentional capture: (a) low probability-the probability occurrence of target location at the collinear column was much less (14%) than the rest of the display (86%), and observers might strategically direct their attention away from the collinear distractor; (b) attentional control setting-the distractor and target task interfered with each other because they shared the same continuity set in attentional task; and/or (c) lack of time to establish the optional strategy. We tested these hypotheses by (a) increasing to 60% the trials in which targets overlapped with the same collinear distractor columns, (b) replacing the target task to be connectivity-irrelevant (i.e., luminance discrimination), and (c) having our observers practice the same search task for 10 days. Our results speak against all these hypotheses and lead us to conclude that a collinear distractor impairs search at a level that is unaffected by probabilistic information, attentional setting, and learning.
显著的干扰项会自发吸引我们的注意力，即使我们有意想要忽略它们。当这种情况发生时，与干扰项接近或重叠的真实目标会受益于注意力捕捉，从而被更快地检测和辨别出来。然而，在一个搜索显示中观察到了一种令人困惑的相反效应，其中一列垂直共线的条被呈现为与任务无关的干扰项[6]。在这种情况下，辨别与显著干扰项重叠的目标变得更加困难。在这里，我们研究了这种效应是否源于已知调节注意力捕捉的因素：（a）低概率——目标出现在共线列位置的概率（14%）远低于显示的其他部分（86%），观察者可能会策略性地将注意力从共线干扰项上移开；（b）注意力控制设置——干扰项和目标任务相互干扰，因为它们在注意力任务中共享相同的连续性设置；和/或（c）缺乏建立最优策略的时间。我们通过以下方式检验这些假设：（a）将目标与相同共线干扰项列重叠的试验比例提高到60%，（b）将目标任务替换为与连通性无关的任务（即亮度辨别），以及（c）让我们的观察者对相同的搜索任务进行10天的练习。我们的结果反驳了所有这些假设，并使我们得出结论，共线干扰项会在一个不受概率信息、注意力设置和学习影响的水平上损害搜索。
