Van der Stigchel Stefan, Meeter Martijn
Utrecht University, Netherlands.
VU University Amsterdam, Netherlands.
J Eye Mov Res. 2017 May 20;10(2). doi: 10.16910/jemr.10.2.6.
Visual attention is guided by the history of selections in previous trials, an effect usually referred to as intertrial priming. The aim of the present study was to investigate whether such priming in visual search is due to a strengthening of the target signal, or the suppression of the distractor signal. In two experiments, we examined the deviation of saccade endpoints in situations in which the target and distractors were presented in relative close proximity. We found both negative and positive priming, irrespective of whether the repeating feature was relevant or irrelevant. This finding is in contrast to previous results with this paradigm, based on which we concluded that visual priming is strictly the result of boosting perceptual target signals. Based on the differences between these experiments, we conclude that the number of distractors is essential in observing negative priming. We propose that negative priming is solely observed when multiple distractors result in either strong inhibition of distractor features, or strong adaptation to them. Whereas positive priming seems to be a robust mechanism, negative priming is only present if there are multiple distractors.
视觉注意力受先前试验中的选择历史引导，这种效应通常被称为试验间启动。本研究的目的是调查视觉搜索中的这种启动是由于目标信号的增强，还是干扰信号的抑制。在两个实验中，我们研究了目标和干扰物相对靠近呈现时扫视终点的偏差。我们发现了负启动和正启动，无论重复特征是否相关。这一发现与该范式之前的结果形成对比，基于之前的结果我们得出结论，视觉启动严格来说是增强感知目标信号的结果。基于这些实验之间的差异，我们得出结论，干扰物的数量对于观察到负启动至关重要。我们提出，只有当多个干扰物导致对干扰物特征的强烈抑制或强烈适应时，才会观察到负启动。而正启动似乎是一种稳健的机制，只有在存在多个干扰物时才会出现负启动。
