Sobel Kenith V, Puri Amrita M
Department of Psychology and Counseling, University of Central Arkansas, United States.
Department of Biology, University of Central Arkansas, United States.
Acta Psychol (Amst). 2018 Feb;183:66-74. doi: 10.1016/j.actpsy.2018.01.003. Epub 2018 Jan 18.
In numerical comparison experiments, participants are presented with two digits that vary in numerical and physical size, and they select the numerically (or physically) larger (or smaller) of the two digits. Response times are typically faster when numerical and physical size are congruent than when they are incongruent, which is called the size congruity effect (SCE). Although numerical size is unlikely to be a guiding feature in visual search, recent studies have nevertheless observed the SCE in the visual search paradigm. To explain this puzzling fact, we hypothesized that the incongruity between a target's numerical and physical size affects visual search primarily when an attended item is compared to the target template in visual short-term memory. In three experiments, participants searched for a target whose numerical and physical size were distinct from non-target distractors. The SCE and shallow search slopes in Experiment 1 suggest that the target's physical size captured attention, and only then did incongruent numerical size interfere with the response. Instructing participants to attend to physical size in Experiment 2 abolished the SCE, suggesting that participants did not analyze the target's numerical size when they could be confident that physical size was a reliable target cue. Presenting each of two possible target digits in blocks as in Experiment 3 enabled participants to load the visual features of shape and physical size into their target template, and once again the SCE was abolished. The three experiments show that the SCE in visual search can be reduced or eliminated by restricting the target template based on specific physical features and thus discouraging participants from analyzing the target's numerical size.
在数字比较实验中，向参与者呈现两个在数字大小和物理尺寸上有所不同的数字，他们要从这两个数字中选择数值上（或物理尺寸上）较大（或较小）的那个。当数字大小和物理尺寸一致时，反应时间通常比不一致时更快，这被称为大小一致性效应（SCE）。尽管数字大小不太可能是视觉搜索中的引导特征，但最近的研究仍在视觉搜索范式中观察到了SCE。为了解释这一令人困惑的事实，我们假设，当在视觉短期记忆中将被关注的项目与目标模板进行比较时，目标的数字大小和物理尺寸之间的不一致主要影响视觉搜索。在三个实验中，参与者搜索一个目标，该目标的数字大小和物理尺寸与非目标干扰物不同。实验1中的SCE和浅层搜索斜率表明，目标的物理尺寸吸引了注意力，然后不一致的数字大小才会干扰反应。在实验2中指示参与者关注物理尺寸消除了SCE，这表明当参与者能够确信物理尺寸是可靠的目标线索时，他们不会分析目标的数字大小。如实验3那样将两个可能的目标数字分块呈现，使参与者能够将形状和物理尺寸的视觉特征加载到他们的目标模板中，SCE再次被消除。这三个实验表明，通过基于特定物理特征限制目标模板，从而阻止参与者分析目标的数字大小，可以减少或消除视觉搜索中的SCE。
