Naber Marnix, Vedder Anneke, Brown Stephen B R E, Nieuwenhuis Sander
Experimental Psychology, Utrecht UniversityUtrecht, Netherlands; Vision Sciences Laboratory, Harvard University, CambridgeMA, USA; Cognitive Psychology, Leiden UniversityLeiden, Netherlands; Leiden Institute for Brain and Cognition, Leiden University Medical CenterLeiden, Netherlands.
Vision Sciences Laboratory, Harvard University, CambridgeMA, USA; Clinical Psychology, Utrecht UniversityUtrecht, Netherlands.
Front Psychol. 2016 Jun 1;7:822. doi: 10.3389/fpsyg.2016.00822. eCollection 2016.
The Stroop task is a popular neuropsychological test that measures executive control. Strong Stroop interference is commonly interpreted in neuropsychology as a diagnostic marker of impairment in executive control, possibly reflecting executive dysfunction. However, popular models of the Stroop task indicate that several other aspects of color and word processing may also account for individual differences in the Stroop task, independent of executive control. Here we use new approaches to investigate the degree to which individual differences in Stroop interference correlate with the relative processing speed of word and color stimuli, and the lateral inhibition between visual stimuli. We conducted an electrophysiological and behavioral experiment to measure (1) how quickly an individual's brain processes words and colors presented in isolation (P3 latency), and (2) the strength of an individual's lateral inhibition between visual representations with a visual illusion. Both measures explained at least 40% of the variance in Stroop interference across individuals. As these measures were obtained in contexts not requiring any executive control, we conclude that the Stroop effect also measures an individual's pre-set way of processing visual features such as words and colors. This study highlights the important contributions of stimulus processing speed and lateral inhibition to individual differences in Stroop interference, and challenges the general view that the Stroop task primarily assesses executive control.
斯特鲁普任务是一种常用的神经心理学测试，用于测量执行控制能力。在神经心理学中，强烈的斯特鲁普干扰通常被解释为执行控制受损的诊断标志，可能反映了执行功能障碍。然而，斯特鲁普任务的流行模型表明，颜色和单词处理的其他几个方面也可能导致斯特鲁普任务中的个体差异，而与执行控制无关。在这里，我们采用新方法来研究斯特鲁普干扰中的个体差异与单词和颜色刺激的相对处理速度以及视觉刺激之间的侧向抑制的相关程度。我们进行了一项电生理和行为实验，以测量：（1）个体大脑处理单独呈现的单词和颜色的速度有多快（P3潜伏期），以及（2）个体在视觉错觉中视觉表征之间的侧向抑制强度。这两项测量至少解释了个体间斯特鲁普干扰差异的40%。由于这些测量是在不需要任何执行控制的情况下获得的，我们得出结论，斯特鲁普效应也测量了个体处理单词和颜色等视觉特征的预设方式。这项研究突出了刺激处理速度和侧向抑制对斯特鲁普干扰个体差异的重要贡献，并挑战了斯特鲁普任务主要评估执行控制的普遍观点。
