Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neurophysiology, Bruxelles, Belgium.
J Cogn Neurosci. 2010 May;22(5):918-30. doi: 10.1162/jocn.2009.21233.
Some objects in the visual field are more likely to attract attention because they are either intrinsically eye catching or relevant in the context of a particular task. These two factors, known as stimulus-driven and goal-directed factors, respectively, are thought to be integrated into a unique salience map, possibly located in the frontal or the parietal cortex. However, the distinct contribution of these two regions to salience representation is difficult to establish experimentally and remains debated. In an attempt to address this issue, we designed several dual tasks composed of a letter reporting task and a visual search task, allowing us to quantify the salience of each visual item by measuring its probability to be selected by attention. In Experiment 1, the salience of the visual search items depended on a combination of conspicuity and relevance factors, whereas in Experiment 2, stimulus-driven and goal-directed factors were tested separately. Then, we used transcranial magnetic stimulation to interfere transiently with the function of the right angular gyrus (ANG) or right FEFs in healthy subjects performing these dual tasks. We found that interfering with the ANG and the FEF function specifically altered the influence of salience on the letter report rate without affecting the overall letter reporting rate, suggesting that these areas are involved in salience representation. In particular, the present study suggests that ANG is involved in goal-directed salience representation, whereas FEF would rather house a global salience map integrating both goal-directed and stimulus-driven factors.
一些视野中的物体更容易引起注意，因为它们要么本身就很引人注目，要么在特定任务的背景下具有相关性。这两个因素分别被称为刺激驱动因素和目标导向因素，被认为整合到一个独特的显著图中，可能位于额叶或顶叶皮层。然而，这两个区域对显著表示的独特贡献很难通过实验来确定，并且仍然存在争议。为了解决这个问题，我们设计了几个由字母报告任务和视觉搜索任务组成的双重任务，通过测量每个视觉项目被注意选择的概率来量化其显著程度。在实验 1 中，视觉搜索项目的显著程度取决于显著性和相关性因素的组合，而在实验 2 中，分别测试了刺激驱动和目标导向因素。然后，我们使用经颅磁刺激在执行这些双重任务的健康受试者中暂时干扰右侧角回（ANG）或右侧额上回（FEF）的功能。我们发现，干扰 ANG 和 FEF 的功能特异性地改变了显著度对字母报告率的影响，而不影响整体字母报告率，这表明这些区域参与了显著度表示。特别是，本研究表明 ANG 参与了目标导向的显著度表示，而 FEF 则更像是一个整合了目标导向和刺激驱动因素的全局显著度图。
