Visual processing of contours and textures

轮廓和纹理的视觉处理

• 批准号: 121713-2011
• 负责人: Kingdom, Frederick
• 金额: $ 4.08万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=569221
• 关键词: Visual; processing; contours; textures

This application is for funds to continue my research into the visual processing of contours and textures. Being able to process the shapes of contours, such as a curved outline of a pear, as well as textures, such as the surface of a folded carpet, is an essential part of our ability to recognize objects and the shapes of surfaces in the visual world. My experiments involve human test subjects viewing large numbers of specially-designed computer-generated test patterns presented on a display monitor and making judgements about them. The particular experimental method I current employ is the 'visual after-effect'. Prolonged viewing, termed 'adaptation', of a particular contour/texture shape causes other contour/texture shapes to appear distorted. By measuring the amount of distortion, a great deal can be learnt about how the brain processes contour/texture shapes. For example, if one takes a simple curved contour and adapts to it, a slightly more curved contour appears even more curved than otherwise. This effect is termed the 'curvature after-effect', and the fact that it happens at all tells us that there are neurons in the brain that are specialized for seeing curves. Thus the curvature after-effect can be used to uncover the details of how the brain sees curves. To take one example of how it can do this, my lab has shown that if the adaptation and test curves are a different colour the curvature after-effect is much reduced (i.e. there is less distortion) compared to if they are the same colour. This tells us that the neurons in the brain that detect curves are 'tuned' for colour, in other words some neurons respond to red curves, some green curves, some blue curves etc. Together with other experiments, my research therefore leads to a better understanding of how the brain sees the shapes of contours and textures.

这项申请是为继续我在轮廓和纹理的视觉处理方面的研究提供资金。能够处理轮廓的形状，如梨的曲线轮廓，以及纹理，如折叠地毯的表面，是我们在视觉世界中识别物体和表面形状的能力的重要组成部分。我的实验让受试者观看显示器上呈现的大量特别设计的计算机生成的测试模式，并对它们做出判断。我目前所采用的特殊实验方法是“视觉后效”。对特定轮廓/纹理形状的长时间观察(被称为‘适应’)会导致其他轮廓/纹理形状看起来失真。通过测量扭曲的程度，可以了解大脑是如何处理轮廓/纹理形状的。例如，如果一个人采用一个简单的曲线轮廓并对其进行调整，那么稍微弯曲一点的轮廓看起来甚至比没有曲线的轮廓更加弯曲。这种效应被称为“曲率后效应”，它的发生告诉我们，大脑中有专门用于看到曲线的神经元。因此，曲率后效可以用来揭示大脑如何看到曲线的细节。举一个它如何做到这一点的例子，我的实验室已经证明，如果自适应和测试曲线是不同的颜色，那么与它们是相同的颜色相比，曲率后效会大大减少(即有更少的失真)。这告诉我们，大脑中检测曲线的神经元是对颜色做出“调整”的，换句话说，一些神经元对红色曲线、一些绿色曲线、一些蓝色曲线等做出反应。因此，与其他实验一起，我的研究使我们更好地理解了大脑如何看到轮廓和纹理的形状。