Watson Poppy, Korjoukov Ilia, Vartak Devavrat, Roelfsema Pieter R
Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA Amsterdam, The Netherlands.
Vision Res. 2013 Jun 7;85:90-103. doi: 10.1016/j.visres.2012.12.010. Epub 2013 Jan 5.
We direct our attention to those visual stimuli that are relevant to our behavioral goals. Some of the visual stimuli that surround us are represented more strongly, because they have a higher luminance contrast. However, selective attention also boosts the representation of visual stimuli. It is not yet well understood how attention and contrast interact. Some previous theories proposed that attentional effects are strongest at low contrast, others that they are strongest at high contrast and yet others that the effects of selective attention are largely independent of contrast. In the present study, we investigated the interaction between selective attention and luminance contrast with a contour-grouping task that provides a sensitive measure of the spread of object-based attention, with delays of several hundreds of milliseconds. We find that the spread of object-based attention is largely independent of contrast, and that subjects experience little difficulty in grouping low-contrast contour elements in the presence of other contour elements with a much higher contrast. The results imply that object-based attention and contrast have largely independent effects on visual processing.
我们将注意力导向与我们行为目标相关的视觉刺激。我们周围的一些视觉刺激表现得更为强烈，因为它们具有更高的亮度对比度。然而，选择性注意也会增强视觉刺激的表征。目前还不清楚注意和对比度是如何相互作用的。以前的一些理论提出，注意效应在低对比度时最强，另一些理论则认为在高对比度时最强，还有一些理论认为选择性注意的效应在很大程度上与对比度无关。在本研究中，我们通过一项轮廓分组任务来研究选择性注意与亮度对比度之间的相互作用，该任务提供了一种对基于对象的注意范围的灵敏测量方法，延迟时间为几百毫秒。我们发现，基于对象的注意范围在很大程度上与对比度无关，并且在存在对比度高得多的其他轮廓元素的情况下，受试者在对低对比度轮廓元素进行分组时几乎没有困难。结果表明，基于对象的注意和对比度对视觉处理有很大程度上的独立影响。
